People who refuse to dance with others because they're too low level for them are called dance snobs around here. There should be plenty of other people who will dance with you regardless of your level. A good leader should be able to adapt to his partner's level. If you're a beginner and he's advanced, he should have enough knowledge and experience to stick to moves that you know and are able to follow. Pulling out every move he knows won't be fun for either of you and it won't look good. So there's really no good reason you can't dance with him if you want to.
You can just ask him to dance if you want to dance with him. There's nothing wrong with women asking men to dance. If you don't want to do that though, just keep dancing with other people. If you look good with other people, the guy you'd like to dance with may notice and ask you to dance. You can also warn him, in either case, that you're a beginner and don't know lots of fancy moves. If you practice and take lessons, you'll improve and your level will go up. So just keep dancing and having fun. :)