How to be less awkward with a girl?

So their is this girl in my school. I met her about a month ago and I'm trying to get to know her better, but the thing is i can't seem to keep a conversation with her. I'm not exactly a good starter, but once I get into a subject I can get a really good flow and she's the exact opposite she can start but can never hold it. I thought that it would work out great but its not so advice? Also took her to this banquet thing at our school as a friend but it was pretty dang awkward there to. It was like a legit 3 hours of just really awkward small talk so please if you have any advice answer below.