I'm 13, 5'3 and weight 177 pounds.. Is there anyway that I can lose at least 40 pounds within 2 months before school starts? (I really want to lose 60 pounds but I don't think it's possible)

Think 5-7 pounds a month. (Why didn't you start this in May?) More than that would be harmful. Walk every chance you get and lay off most foods that are white -- flour products, sugar, potatoes, rice. Cauliflower is fine. Eat lots of fresh veggies, lean meats,and most fruits. And a doctor's input would be nifty.

Try to go with foods that are fresh home cooked and Mediterranean diet. Processed, packaged and frozen foods are full of chemicals that mess up your metabolism. The nutrients are not good quality. Even yogurt and many health bars are not good. Stay away from diet or anything that says no sugar added *(but contains artificial sweeteners)