Exercise is great for all these things above. It will only take 1-2 hours a day for you to get enough exercise for the day. Just by doing that you will get many benefits for your body including improving your confidence. Most of this stuff helps with school or a job so there is no reason this would not be a good thing for anyone. The key to keep doing this and not lose motivation is to have a friend with you working out. That friend will push you to go if you are feeling lazy and will turn that boring experience into a more enjoyable one if you have a tough time working out. Overall, I see this as a good thing for anyone and personally helped me a lot.