There were three times when Jesus was asked how to have eternal life.
The first time was when the rich young ruler came to him. Jesus quoted several of the commandments. The ruler said "I've kept those from my youth". Jesus said sell all your goods and follow me. The rich young ruler went away sorrowful. Effectively even thought the rich young ruler had lived an extremely good life by human standards, Jesus had focused him on "Have no other God before me". And he failed.
The second time a lawyer asked. Jesus replied what's written in the law?" The Lawyer replied "Love God and Love your neighbor as yourself." Jesus said, "Do this and you will live." The lawyer "seeking to justify himself" asked "who is my neighbor?". Which led to the parable of the good Samaritan. Again Jesus answered obey the law, but in such a way that it showed the seeker his faults.
The third time was Nicodemus. To Nicodemus, Jesus said, "You must be born again."
There are two ways to get to heaven. Never sin, or be forgiven. Scripture tells us none are righteous, nobody has done or will do the first, except for Jesus.
An English translation of the Holy Father's letter is here: Pope Francis' Letter to the Founder of "La Repubblica" Italian Newspaper.
Also see post #11, here.
The Catholic Church has always taught that if you lived your life according to the Beatitutes, and you were not exposed to Christianity, that you can still go to heaven. This is all Pope Francis is trying to say. On the otherhand if you were exposed to the teachings of Jesus Christ and ignored him and turned away from you, you don’t go to heaven. Pretty simple.