Im 5 foot 9 inches tall you weigh 245 pounds and how can o lose 40 pounds in 4 months?

It is a good idea to see your family doctor. They can help alot. They will tell you which foods to eat and which to cut back on and how active you should be as a 13 year old. Most of all do it to be healthy. Don't do it because of peer pressure. Be happy with who you are