Start running the mile everyday and try doing it twice a day. One in the morning one in the afternoon. Also don't excise at night before you go to bed. That's bad and makes you gain weight. And if you don't want to leave your yard run the miles around your house. Get when of those weird little...
There are tons of sports you can play. If none the common ones are right for you go for the uncommon.
You could try fencing. (Sword Fighting)
I started fencing when I was 11 or 12 and it's really fun. It works muscles you don't usually use and helps with balance. It makes you move around a lot...
