Whey protein does not lead to acne.
Also, Whey is a protein supplement and is not used to gain weight unless it has a weight gainer in it, or if you are taking it with a weight gainer. Protein supplements are taken to help you gain lean muscle mass along with working out (and other supplements if that is what you are doing). If you would like some information on some weight gainers, I could give you a few different things to try if that is allowed on these boarRAB?
Good Luck!