Get a medical checkup first.
Find out what's stopping you from losing weight.
If there's nothing wrong, just eat less... and spend less time on your pc.

Food Rich Fiber
One of the keys to successful dieting (losing weight) is to eat foods rich in fiber. Consumption of fibrous foods is recommended for consumption during the day or night. These high-fiber foods can be obtained from fruits and vegetables. Pure fruit such as pear, banana, papaya, and guava. Vegetables such as broccoli, squash, spinach, turnips, potatoes, sweet potatoes, cauliflower, red cabbage, and green vegetables.