Matthew 19:14.
But Jesus said, suffer little children and forbid them not to come unto me. For of such is the kingdom of heaven.
This passage makes us know that little children are destined to go to heaven. If they die, they will be counted worthy of entering the heavens. But if they exceed the years of infancy, being now teenagers or reaching the age of adolescence, God knows where they are
going. But if we do the will of God, we are certain of going to heaven irrespective of our ages.
Matthew 7:21
Not everyone that says unto me, Lord, Lord, shall enter into the kingdom
of heaven. But he that doeth the will of my father, which is in heaven.
If one reaches the age of adolescence, where you are fully aware of your actions, we have no excuse. We are expected to do the will of the father in heaven, all the days of our lives. Anyone that doeth the will of the father, which is in heaven, is going to heaven. But anyone, even if he is praying and calling upon the name of the Lord just as narrated passage above but does not the will of God will enter the kingdom of heaven.
But for those who are willing to do the will of God they are assured of entering into His kingdom. The bible lets us know that God is not a respecter of any man. So regardless of your status, we are all expected to live the life He has called us to live. God bless you.