Lesbian Relationship Questions

So, I am in my first relationship with a girl, and I'm very curious as in what's gonna go on in my relationship. How do we have sex? I don't know how to do it... Also, I have a big issue. I'm a female, but I consider myself more masculine, as in looks, behavior etc. So I'm not sure if I would feel comfortable with her touching breasts and being treated like a woman, and gosh. it's very difficult and don't know what to do. Advice?