Lose weight during school?

I'm very overweight, and next year ill be in the 9th grade. I'm going through a lot of stress w/ my parents, and moving back to the states. After school im really tired, and do homework then read, it's usually raining here, or just hella hot. I've veen thinking about going on a no carb, or no junk food diet, but what would be some other, needed tips? I'm 14, 5'4 and 222, help me please?
Lose weight during school?
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