Losing weight and getting healthier? Any advice on how to do so?

you need to get at least 7 hours of sleep if not more. because you are so young you need it. also eating before you go to bed can cause you to gain weight, so don't eat anything for at least 2 hours before you go to bed. when i was younger, i started walking a lot to tone up and it really worked. if you keep a good pace going it should help some. keep playing your other sports and make minor altercations in your diet and you will do fine. good luck!