The bible is clear about that it exist good and evil people, and when the good people dies, they go to heaven,.. and when the evil people dies, they will later go to hell (where they will get measured up a punishment, equal to their degree of evilness).
To avoid getting to hell, one only need to be a good person, where one have a good living rule for other people (to treat other people good / right).
Even if one are a good person, one can fall and do evil things unfortunately,.. but what is important, is that one are a good person at the bottom, because that means that one’s soul is good (that one haven’t damaged one’s soul).
«Do not marvel at this; for the hour is coming in which all who are in the graves will hear His voice and come forth—those who have done good, to the resurrection of life, and those who have done evil, to the resurrection of condemnation.» Jesus quoted, in John 5.28-29
«“When the Son of Man comes in His glory, and all the holy angels with Him, then He will sit on the throne of His glory. All the nations will be gathered before Him, and He will separate them one from another, as a shepherd divides his sheep from the goats. And He will set the sheep on His right hand, but the goats on the left. Then the King will say to those on His right hand, ‘Come, you blessed of My Father, inherit the kingdom prepared for you from the foundation of the world: for I was hungry and you gave Me food; I was thirsty and you gave Me drink; I was a stranger and you took Me in; I was naked and you clothed Me; I was sick and you visited Me; I was in prison and you came to Me.’
“Then the righteous will answer Him, saying, ‘Lord, when did we see You hungry and feed You, or thirsty and give You drink? When did we see You a stranger and take You in, or naked and clothe You? Or when did we see You sick, or in prison, and come to You?’ And the King will answer and say to them, ‘Assuredly, I say to you, inasmuch as you did it to one of the least of these My brethren, you did it to Me.’
“Then He will also say to those on the left hand, ‘Depart from Me, you cursed, into the everlasting fire prepared for the devil and his angels: for I was hungry and you gave Me no food; I was thirsty and you gave Me no drink; I was a stranger and you did not take Me in, naked and you did not clothe Me, sick and in prison and you did not visit Me.’
“Then they also will answer Him, saying, ‘Lord, when did we see You hungry or thirsty or a stranger or naked or sick or in prison, and did not minister to You?’ Then He will answer them, saying, ‘Assuredly, I say to you, inasmuch as you did not do it to one of the least of these, you did not do it to Me.’ And these will go away into everlasting punishment, but the righteous into eternal life.”» Jesus quoted, in Matthew 25.31-46
The reason why good people goes til heaven, even if we have sinned, is because Jesus took the punishment for our sins.
«The next day John saw Jesus coming toward him, and said, “Behold! The Lamb of God who takes away the sin of the world!» John 1.29
«For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.» Romans 6.23