I think the best thing you can do is have your parents feed you healthy foods, tell them to stop buying junk food, and ask your parent's if you can get involved with recreational soccer. Soccer is a very hard sport to dislike at your age, and I wish I could have balanced it with Basketball. Soccer is a lot of running, but at your age it won't be anything that you can't do, plus you'll get in great shape in NO TIME at all.