Do your parents have healthy food around the house? That would be a start. Ask your parents to buy more healhful food. Always keep some fruit and or vegetables with you for snack, so you don't get hungry and eat junk. Make it a goal to walk everyday for 1 week (starting today until next Friday) and starting TODAY, do lunges, squats, push ups, and jumping jacks. Or you can dance, just keep moving for 20 minutes. After a week you should notice your energy level getting higher. And if you eat good and exercise by 1 month you should see some results.