Many girls your age become interested in wicca, witchcraft, what have you. What should you do?
Well..Bob is right indicating that you are too young to be initiated into any reputable coven or group. That doesn't mean you can't do some reading and get a feel for what may be coming should you continue. I recommend you speak with Lady Mimi at Esoterica. She has met many young girls in your position and should be able to give wise counsel. She also has a wide selection of books that will get you started, such as the Silver Ravenwolf books or perhaps those by Scott Cunningham.