As a Christian, I was taught that there are several ways to get into Heaven / avoid Hell.
The methods depend on
(1) whether you have heard or read or otherwised observed the Good News. and/or
(2) whether you are a devout Jew.
The pagan way:
Lack of meeting either condition means that you are judged on your own inherent goodness (innocence) according to whatever standard God imposes. I was not taught the specifcations of this standard, but the Bible indicates that it would follow the lines of the 2 greatest commandments Jesus speaks of in Mat 22:34-38. This is why Jesus performed miracles for Romans and Samaritans and not only for other Jews as performed through the prior prophets in the Old Testament. God wanted more people to make it to Heaven. This is not easy, but doable for pagans who have been denied the Good News of Salvation through Christ. It is also considered much easier for children and babies to enter Heaven because willful sins are the realm of adults who are assumed to have inherent knowledge of good and evil. Innocence is considered to fade as the child reaches adulthood.
The Jewish way:
Grown up Jews can make it into Heaven by keeping the entirety of the Jewish law. This is considered an impossibility, accomplished only by Jesus. Even some of the prophets were unable to keep the entire law, yet they are widely considered to be in Heaven for faithfully bearing witness to Israel and then getting soon killed by the mobs and/or kings who refused God’s message. They are considered by Christians to be honored messengers of the Lord. Keeping all of the laws also involves massive sacrificial offerings on a regular basis to redeem a lifetime of sins. The heart behind the sacrifice must show a tremendous love of the Lord. The sacrifice can not just be something you were about to throw away. It should be something you really wanted to keep or use, but your giving it to God means you really loved God. Genesis 4 highlights this; Abel gave the the best of the firstborn of his flock while Cain only gave “some fruits of the soil”. We infer that while giving fruit is nice, the Lord wants our best, and that is why Cain’s offering was disfavored. It is widely believed that King David is in Heaven for having the right heart for the Lord, while most others are not, notably King Solomon, who was a wiser ruler, and wrote more of what was compiled into the Bible. Both kings committed great sins, but David gained mercy from the Almighty.
The Christian way:
Christians meet all of the following:
1> They have received the Good News of God giving his only begotten Son Jesus as the ultimate sacrifice for their individual sins.
2> They realize the weight of their own sins, and repent of them, or at least strive towards the repentance.
Sins include things not done when they should have been. The same applies to the Hebraic sins where inaction can be sin where action is required.
3> They accept Jesus’ sacrifice to wash them of their past sins. This is to show faith that Jesus has the power to do so.
4> They accept Jesus as Lord and Savior. This means giving up the old life and faithfully taking up the new one of honoring Jesus. They share the Good News with others as an act of love.
The Christian way of reaching heaven is considered to be much easier than the other ways.
Christians also believe that Armageddon will happen after all of the world has heard the witness of the Good News. There are communist and heavily Muslim parts of the world where this is denied to the children. We can also include certain sects even in the USA, where media restrictions allow a charismatic cadre to dominate the affairs of the group.