There are no magic tricks to loose weight. You must cut down on fats drastically, especially trans fat and get your butt going doing daily exercise, walk, run, swim and sports. Opra Winfrey did it, why can't you?
Don't listen to your dad's insults, he probably is just sad to see you in that state. You are the leader of your own destiny. Get off the computer and out you go walking and walking.