I am skinny and i am currently taking good diet. but my faceis very bony. my cheeks are depressed inside and the cheek bone seems large. how can i fill the cheek?

Chew gum: First, make sure you don't have consumption (tuberculosis). Secondly, could you have protein malabsorption? Adding different sources of protein may help. If it's just about the face, chewing gum builds up your chewing muscles especially the masseter, which should fill in your hollow cheeks. Good luck !

Gain weight: As you get older it will start filling it. But the fastest way to do it is to gain weight.

Avoid procedures: Try to avoid any filling procedures calculate your bmi if its less than 20 you should consider gaining some weight if can't discuss with your general doctor.