Can Protein Supplement Reduce The Discomfort In Leg And Toning?

hii, i'm santosh i have a question regarding my left leg its really bothered me a lot, my left leg muscles are not well toned comparing to the right one,its a bit skinny. so, pls tell me is there any treatment to develop muscle for left leg, i know i need to exercise for that but the develoment of muscle is not so good, i beleve if i take some protein supplements for my left leg will it work.. pls suggest me