In Buddha's Middle Discourses (Majjhima Nikaya), Buddha is asked by one of his followers about his view on the eternality and infinitude of the world:

Majjhima Nikaya - Aggivacchagotta Sutta 3-6

3 "How is it, Master Gotama, does Master Gotama hold the view: 'The world is eternal: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The world is eternal: only this is true, anything else is wrong.'"
4 "How then, does Master Gotama hold the view: 'The world is not eternal: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The world is not eternal: only this is true, anything else is wrong.'"
5 "How is it, Master Gotama, does Master Gotama hold the view: 'The world is finite: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The world is finite: only this is true, anything else is wrong.'"
6 "How then, does Master Gotama hold the view: 'The world is infinite: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The world is infinite: only this is true, anything else is wrong.'"

Buddha's response above is essentially to refuse to answer, or take a position on either question. He denies that he holds the view that the world is eternal, or that it is not eternal. He denies that he holds the view that the world is infinite, or that it is finite. This means that he has no view on these questions - he is agnostic.

Buddha's follower continues with his questions, proceeding to ask about the relationship of the body to the soul, and whether an enlightened person (Tathagata) continues to exist after death:

Majjhima Nikaya - Aggivacchagotta Sutta 7-12

7 "How is it, Master Gotama, does Master Gotama hold the view: 'The soul and the body are the same: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The soul and the body are the same: only this is true, anything else is wrong.'"
8 "How then, does Master Gotama hold the view: 'The soul is one thing and the body another: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'The soul is one thing and the body another: only this is true, anything else is wrong.'"
9 "How is it, Master Gotama, does Master Gotama hold the view: 'After death a Tathagata exists: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'After death a Tathagata exists: only this is true, anything else is wrong.'"
10 "How then, does Master Gotama hold the view: 'After death a Tathagata does not exist: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'After death a Tathagata does not exist: only this is true, anything else is wrong.'"
11 "How is it, Master Gotama, does Master Gotama hold the view: 'After death a Tathagata both exists and does not exist: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'After death a Tathagata both exists and does not exist: only this is true, anything else is wrong.'"
12 "How then, does Master Gotama hold the view: 'After death a Tathagata neither exists nor does not exist: only this is true, anything else is wrong'?" "Vaccha, I do not hold the view: 'After death a Tathagata neither exists nor does not exist: only this is true, anything else is wrong.'"

Notice that just as with the eternality and infinitude of the universe, these are extremely fundamental questions about reality. And, similarly, Buddha remains agnostic, refusing to take any position.

Likewise, in the Culamalunkya Sutta of the Middle Discourses, Buddha is asked the same set of questions by a different person, responding:

Majjhima Nikaya - Culamalunkya Sutta 7-10

7 "Therefore, Malunkyaputta, remember what I have left undeclared as undeclared, and remember what I have declared as declared. And what have I left undeclared? 'The world is eternal' - I have left undeclared. 'The world is not eternal' - I have left undeclared. 'The world is finite' - I have left undeclared. 'The world is infinite' - I have left undeclared. 'The soul is the same as the body' - I have left undeclared. 'The soul is one thing and the body another' - I have left undeclared. 'After death a Tathagata exists' - I have left undeclared. 'After death a Tathagata does not exist' - I have left undeclared. 'After death a Tathagata both exists and does not exist' - I have left undeclared. 'After death a Tathagata neither exists nor does not exist' - I have left undeclared.
8 "Why have I left that undeclared? Because it is unbeneficial, it does not belong to the fundamentals of the holy life, it does not lead to disenchantment, to dispassion, to cessation, to peace, to direct knowledge, to enlightenment, to Nibbana. That is why I have left it undeclared."
9 "And what have I declared? 'This is suffering' - I have declared. 'This is the origin of suffering' - I have declared. 'This is the cessation of suffering' - I have declared. 'This is the way leading to the cessation of suffering' - have declared.
10 "Why have I declared that? Because it is beneficial, it belongs to the fundamentals of the holy life, it leads to disenchantment, to dispassion, to cessation, to peace, to direct knowledge, to enlightenment, to Nibbana. That is why I have declared it.

Above, Buddha said that he remained agnostic on many matters pertaining to the fundamental nature of reality because "it is unbeneficial, it does not belong to the fundamentals of the holy life, it does not lead to disenchantment, to dispassion, to cessation, to peace, to direct knowledge, to enlightenment, to Nibbana". Instead, according to himself, he only taught on the origin of suffering, and the means of attaining the cessation of suffering.

Buddhism, therefore, can never be anything more than a philosophically deficient religion. There can be no answer, or even speculation, on such things as where the universe came from, the nature of a person's soul, or even existence after death - all fundamental, vital questions, which define how a person views reality. The founder of the religion has declared such topics "unbeneficial", and elsewhere "beset by suffering, by vexation, by despair" (Aggivacchagotta Sutta 14).

The problems created by this approach abound:

• Forbidding to speculate on whether the universe had a beginning is forbidding to speculate on whether there is a Creator of the universe, or whether the universe has no Creator, because if the universe was created by a transcendent Creator, then it had a beginning, and so that would be the position one would have to hold. But, without holding the position that a transcendent Being exists, and that Buddha received a commission from that transcendent Being, why should anyone care about Buddha's claims? On what basis does Buddha claim that we reincarnate? On what basis does Buddha claim that cessation of desire can stop that process? The reason why Christians care about what the prophets said is because the Creator of the universe spoke through them (Hebrews 1:1-3). Absent that, there is no reason whatsoever to believe any of Buddha's claims, as he is not the ultimate authority, nor did he claim to be commissioned by the ultimate authority
• Forbidding to speculate on whether the soul and the body are the same is forbidding to speculate on whether there is such a thing as a soul, or if a person is only their body. However, though Buddha denied that we have a unchanging soul (Anatta), his own teachings logically require that we have a soul, separate from the body. A body can be buried, cremated, and so on, but it is material. Buddha taught that somehow, a person's past lives are affecting their present life. This requires a non-material component to a person, which remains identified with that person after death, which is a good working definition of a soul. So, it does not make sense to declare consideration of such a concept "unbeneficial", when his own teachings demand, at the very least, a similar concept in order to make any sense at all
• Forbidding to speculate on whether one who reaches enlightenment continues to exist after death is forbidding to speculate on the final results of following Buddha's religion. But, if the enlightened person does not exist after death, then whatever force created us wanted us to: (1) exist, (2) learn not to desire anything, then (3) cease to exist - which is absurd, and pointless. Therefore, only the option that an enlightened person continues to exist seems sensible. But, this state obtained by an enlightened person after death would need to be one in which there is no desire, forever - otherwise, they would become unenlightened, and need to repeat Buddha's method in that other world, repeating that process for all eternity, which hardly seems like Nirvana. How then, can any Buddhist refrain from desiring this eternal, perfect bliss, and feeling attachment to it, here on earth? And how would such a desire for this post-Nirvana state not prevent them from obtaining Nirvana?
• Buddha appears to have found a pragmatic method to stop his being tormented by desire, which he codified in the Noble Eightfold Path. Anything that infringed upon what he considered to be this state of bliss, he appears to have declared irrelevant, and to be avoided. However, on what basis does Buddha declare that something which causes desire must be avoided, beyond appealing to his own doctrine that desire is the cause of suffering? A Buddhist cannot, from this circular basis, refute other proposals for the nature of reality - such as a Creator having made mankind, and having made a situation in which some desires and attachments, for instance - the desire to live forever with God, the desire to know God, and the desire to love and be with others - are beneficial and right for that creation (Acts 17:26-27), rather than a source of suffering

Conclusion

Buddha did not have answers to many of life's most important questions, because he created an errant, deficient philosophy, which was unable to accommodate many of life's most important questions.

Consequently, there are no answers in Buddhism. A person's origins, nature, and fate are all purposefully forbidden to be speculated on, lest they distract from the method that the religion's founder insists, based on his own authority, will solve a person's problem of Samsara (rebirth), which he insists takes place, also based on nothing more than his own authority.

The contrast of this philosophy with richness of the true God, who has infinite love for mankind, and made them for the purpose of having them share in that love, cannot be more extreme. This is why, when confronted with the true God, and His love for them, so many Buddhists have left their religion, valuing coherence and truth more than the vain philosophy of their forefathers:

Jeremiah 16:19

19 O LORD, my strength, and my fortress, and my refuge in the day of affliction, the Gentiles shall come unto thee from the ends of the earth, and shall say, Surely our fathers have inherited lies, vanity, and things wherein there is no profit.