Hello, I'm a skinny 21 year old guy (5'10, 143 pounds or less aprox; my goal is muscle gain of course; I've been following an exercising routine for 4-5 days now; I don't measure my calories but I try to eat enough fruits, bread, milk, nuts and seeds, and pasta/chicken/meat/fish depending on the day; I have no injuries) I have a fast metabolism, I eat a lot but don't gain weight (or at least, before starting I hadn't been gaining any weight) I've seen a bit of progress in general which my classmates have pointed out. I've been exercising 3 days a week, doing squats, deadlifts, overhead press and bench press, and also adding in ab and calf exercises, I do them all the same day. My question is, do I need to train daily? I've read in a few sites that in my case I must workout 4 days a week maximum. What other exercises should I add beside those I said if I want a really proportionate body? And should I split them or do them all the same day? How often should I switch up my routine?
Thanks in advanced! I feel kind of frustrated with so much info in the internet that only makes me confused.