How do I loose weight help?! In two weeks?

I''m 13 and please don't suggeset any running or outside activity because the weather is horrible outside and my height is 5''3.2 and I weigh 104.2 my diet on a school day is usalllly nothing in the morning or at school and then I get home and make a sandwhich and then eat dinner so like two meals only but now wer have two weeks of I want o loose weight new diet plan that well help loose weight or somehting anythign will help Also My prombelm ares are mostly my stomach my arms my thighs and my I just want to drop a couple of punds and also How can I not gainm weight each year I gain weight like 4-5 punds are more than that! please help me thankyou!( I'm a girl)