There's this girl named Hannah and she's with this guy that is my best friend but she said she likes me a lot and she's dating him so I don't understand if she's getting tired of her current boyfriend or what because she always hangs with me and we always see each other and there's always something to talk about between is what should I do?

You should honor your friendship with her boyfriend, and you should realize that if she wanted to be with you, she'd break up with him. The fact that she hasn't, speaks volumes about how she feels for you.

Bottom line, she's in a relationship, which means she's off limits.