What are the best supplements/food to help promote muscle growth and development? i am very skinny.

Genetics: Some individuals are genetically skinny and protein supplements or weight training may not increase their muscle mass. If you are otherwise healthy, being skinny is not a disease. Eat a mixed diet of fresh vegetables, fruits, whole grains, nuts; low in saturated fats; and exercise at least 30 minutes a day and do not fret about your skinniness, it is probably a good thing.