Becoming Healthy.

Patient: Considering Im an overweight girl that goes to school 7:00 am to 5:00 p.m and have to do homework 5-7p.m and have 1 hour of free time of the whole day monday thru friday. How can i lose weight? what should i do? I Do know of course, exercising and eating healthy. But what exercises are most effective and can be done within an hour? and eating what type of foods are best to become healthy? Thank you for your time. God Bless you, just need some help to become healthy.