Don't eat late at night, don't starve yourself just eat smaller portions, drink more liquids than you eat actual food. Also don't drink or eat anything with more than 15 grams of sugar in it. Walk, again more liquids..Everyone no matter what size should never comsume more than 2,000 calories per day. Don't snack or have big meal and take a nap right away..eat often but small meals and shut off the eating after 7pm. You should lose weight, unless something medically is preventing it.
Your calorie intake will be different depending on gender, physical attributes, such as height, weight and age. Calories are energy used by our bodies to carry out basic functions. I would suggest that you consult your healthcare for more professional help.