Hi guys. I know it sounds crazy, and unhealthy, but I want to lose 20 pounds by September 4. I'm way willing to do less, but I want to do 20 asap. Please tell me something that isn't extreme, but that will work! Thank you :)

I'm 13, 5'3 and 130

The most you could possibly lose would be around 5 kg's/10 pounds.
You'll need to drastically reduce your calorific intake and increase your aerobic activity.
(Less food more excersise)