Are there any ways to get fatter without eating food or medicine? i am eating a lot of food lately, but i still have not gained any weight.

It may take time: I suppose it's hard to wait, but if you keep eating healthy foods in normal size servings, you should reach a good weight unless there is something wrong. That might mean a doctor's visit to to find out why. Does your mom or other people think you need to gain weight too? Do you feel okay in general? These matter too. Be patient, eat well and get enough rest and enough exercise. It helps!