What would be the absolute minimum I could eat to get thin?

I'm 5ft3 and weigh almost 9 stone (So about 119 lbs maybe) and I feel fat, not obese but fat. What is the absolute minimum I could eat a day to lose maybe 2 or 3 stone quite quickly? I want to be thin like my friends but I don't want to die from not eating. I'm not good with diets so I'd rather just stop eating as much than eating salads and stuff. I usually don't have breakfast because I don't have the time, I eat a little bit of lunch when I'm at home at the weekends but at school I usually don't eat any, then I have tea at home which is generally quite a big meal but I'm still fat and wobbly and I hate it.