What's the best whey protein to take for some one with a fast metabolism?

I'm skinny, eat a lot of food like grain, fat food, and lots of meats and only gain 3 pound but of bad fat last time I checked. I work out 20 min cardio and lift dumbbells and no results of lean muscle gain for the past 7 months.. Please help I want to take protein but don't know which one cause I have a fast metabolism.