I am 19 5'3" and 130 pounds, i am not comfortable with my weight anymore. what is a good diet plan to lose 15-20 pounds?

Don't diet: You are too young to get caught up in dieting. Make some basic changes to what you eat by eliminating foods that have added sugar or high fructose corn syrup, refined flours, etc. And eat more whole foods like fruits, vegetables, nuts, beans, seeds, whole grains, and fish like wild salmon. Go easy on meat, dairy, even the low fat variety, oils, creams, etc. Finally, take lots of brisk walks.