How do I get her to know that I’m into her?

I’m sixteen and the girl I like is seventeen, so different grade. I joined this club at my high school that supports LGBTQ+ and shes in it so I always sit next to her and try to start a conversation. She is so sweet, funny, and overall an amazing girl. The problem is I don’t think she knows I’m into girls, and I don’t know how to get over the friend line w/o making it awkward. I just want to ask her out, hold her hand, and have a good time! its just hard when you aren’t out to anyone.. help?