What can i do to LoSe weight?

I am 16 and i weigh 158.5 my height is 4ft.11in . So i am really short and over weight for my size and age.i try doing exorcise but i just give up and eating right is hard. i cant keep up with it. i want to lose at least 50 pounds. I don't know what to do!!!! i try doing programs but almost everyone program said i need to be 18 years old. can someone help me!!!!