Human: My dumb kid says he's an atheist. How do I fix him before he goes to hell? Assistant: 
You can’t “fix” atheism. Also, if he has chosen to not believe, that is not a “wrong” choice, just a different one. If you don’t believe, that’s also perfectly OK, even though some people feel that atheism is “wrong.”   You can support him in being his own person and make your own beliefs about how to behave, though!