Acts 17:30
30 And the times of this ignorance God winked at; but now commandeth all men every where to repent:
This verse, as with almost every verse that uses the word "repent", is occasionally used to teach that unless someone "repents of their sins", then they will go to Hell when they die.
In context, the Apostle Paul is preaching to the "men of Athens" (Acts 17:22), who lived in a city "wholly given to idolatry" (Acts 17:16), even building an altar to "The Unknown God" (Acts 17:23), just in case they had missed one.
Paul uses this as a launching point for preaching to them about the true God, in distinction from their idols:
Acts 17:26-30
26 And hath made of one blood all nations of men for to dwell on all the face of the earth, and hath determined the times before appointed, and the bounds of their habitation;
27 That they should seek the Lord, if haply they might feel after him, and find him, though he be not far from every one of us:
28 For in him we live, and move, and have our being; as certain also of your own poets have said, For we are also his offspring.
29 Forasmuch then as we are the offspring of God, we ought not to think that the Godhead is like unto gold, or silver, or stone, graven by art and man's device.
30 And the times of this ignorance God winked at; but now commandeth all men every where to repent:
Therefore, what humanity is being commanded to "repent" of, in context, is idolatry and false religion. That's all the verse in question says. It does not say that someone has to behave to some nondescript degree of holiness for their entire lives - or make a commitment to do so, and so on - to get to Heaven. Such a view totally nullifies the entire New Testament, as is covered at length in You Do Not Have to Repent of Your Sins to be Saved.
They are being commanded to "repent" - that is, to "turn" - from their false belief system, just like the Apostle Paul speaks of the Thessalonians having done:
1 Thessalonians 1:9
9 For they themselves shew of us what manner of entering in we had unto you, and how ye turned to God from idols to serve the living and true God;
This is what the Apostle Paul preached everywhere he went. Later in the book of Acts, he recounts this fact, and associates the "turning" that he preached with "faith":
Acts 26:18-20
18 To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God, that they may receive forgiveness of sins, and inheritance among them which are sanctified by faith that is in me.
19 Whereupon, O king Agrippa, I was not disobedient unto the heavenly vision:
20 But shewed first unto them of Damascus, and at Jerusalem, and throughout all the coasts of Judaea, and then to the Gentiles, that they should repent and turn to God, and do works meet for repentance.
From the above, we see that wherever the Apostle Paul went, he preached that people should repent, and then do works fit for that turning to God from idols.
Doing the "works fit for repentance" (verse 30) - living consistently in light of the fact that they believe in Jesus - is something that every believer "should" do (Ephesians 2:10), but attempting to quantify the extent to which a believer must do them in order to "prove" that they "truly repented" from unbelief is essentially trying to quantify the extent to which a person can be a hypocrite. If any believer on this planet doesn't reckon themselves a tremendous hypocrite, they have a woefully low view of God's righteousness and standard (Matthew 5:48), and a dangerously prideful view of themselves.
In a Biblical theology that includes the concept of rewards for service done after Salvation, we can rightfully recognize that we all live on a spectrum of hypocrisy, and will also be rewarded on a spectrum accordingly. However, once this spectrum is taken away, the outcome becomes binary - Heaven or Hell - and so the question becomes, "what's the cutoff"? This is why assurance is impossible in the many brands of "repent of your sins" false Christianity, and why they terminate in works Salvation.
This verse simply teaches that God is going to be harsher on judging idolatry in the New Testament times, and stresses the urgency of believing in Jesus Christ, rather than idols.