Is it possible for dandruff/dry scalp to cause balding/thinning hair for a 21 year old? (photo)

Ever since I was around 13, I've had bad dandruff and a dry scalp, and thus, have created bad habits of scratching my scalp a lot. Recently, I've stopped, as I don't want to lose any more hair, I use Head and Shoulders, and a tar based shampoo, I also put coconut oil on my scalp now. I would like to know if dandruff, dry scalp, and itching can cause balding, and if so, is it temporary, the hair restorable? 21 is way too young for me to have to deal with this.