I believe in Jesus and go to church sometimes and all that, but I don't think we can know if we're going to get to heaven until we actually die. I think we just have to do the best we can, and hope everything will turn out OK in the end.
If our salvation depended only on us, and depended only on our ability to be good enough to convince God He ought to let us into heaven, then you’d be right. The reason is because we’d never know if we’d been good enough until it was too late.
But our salvation doesn’t depend on us; if it did, no one could ever be saved. The reason may startle you, but it’s very important for you to understand: God’s standard is nothing less than perfection. God is absolutely holy and pure, and even one sin would be enough to keep you out of heaven. And who among us has never sinned? No one; we all sin every day, both through things we do that are wrong, and through things we fail to do that are right. The Bible says, “There is no one righteous, not even one…. For all have sinned and fall short of the glory of God” (Romans 3:10, 23).
How then can we be saved? If our salvation doesn’t depend on ourselves, on what does it depend? The Bible’s answer is clear: it depends solely on Christ. He was without sin, but on the cross all our sins were laid on Him, and He took the judgment that you and I deserve.
Turn to Christ and trust Him alone for your salvation. God’s promise is for you: “Believe in the Lord Jesus, and you will be saved” (Acts 16:31).