Do more exercise, such as running, playing basketball and badminton, skipping rope, or go to the gym to do some exercise in a planned way. Be sure to persist. Persistence is very important. And don't eat pizza, hamburgers and high-calorie junk food at roadside stalls, and drink less drinks, especially carbonated drinks. 13 years old, it is best not to go on a diet to lose weight, but you must pay attention to your diet and don't eat too much high-calorie junk food, especially fried food. You can eat more foods high in protein, such as bean products, dairy products, chicken breast and fruits and vegetables. I recommend you to download an APP called "Mint Health", which contains diet, fitness videos, and daily calorie intake calculation. These are all better softwares tailored to your own needs. In short, it is very painful to keep your mouth shut and open your legs. Losing weight can only be effective if you stick to it. Coke and sprite really can't be drunk every day.