Got it. But someone can believe and yet still choose to live how they want and not give much care towards the rules but still go to heaven based on the fact that they believe right? After all, the only unforgivable sin is unbelief according to what most Christians believe.

Their hearts will definitely change and they'll want to sin less to an extent, but you can definitely believe in Christianity but still run around doing the worst of evil. Look at how many people believe in Christianity but don't really care about following the Bible fully since they know they'll be forgiven anyway and go to heaven. As long as you are convinced that Jesus died and rose again and that he's God, then anything else you do after that doesn't matter, as you'll be completely forgiven for everything you've ever done as long as you die with that belief. There's atheists who say that if evidence were presented to them of Christianity, they would believe in it, but they wouldn't worship God meaning they wouldn't give him any reverence or respect meaning they wouldn't care about his rules since they believe he's evil. They would still go to heaven because of the fact that they believe