This girl I like hates religion, what should I do?

If you want a relationship with her to ever be possible, then you should clarify things. You can say to her that you were joking when you said that you hate bis and s and that you like girls. You can tell her that when she said that she hates your beliefs it shocked and hurt you because you didn't realize that she was so anti-religion. You can say that whether she likes it or not your religion is a part of who you are just like her being bi is a part of who she is. I think that if you talk to her about it and she seems remorseful about what she said or is at least curious to know more about you or your religion then you might still have a chance at a romantic relationship with her or continued friendship. If she seems to stick to her narrow-minded beliefs then you might as well let go and move on.