You should take vit c everyday. You need a fairly large amount. I take asorbic acid powder. 2-6 grams a day. IT is also very cheap. Do a search on the net for the benefits of vit c, there are to many for me to type.
I don’t think Vit C actually heals the cells. It has anti-oxident properties and helps prevent damage to them and keep them in good condition.
I think 2-6 grams of Vit C a day is too much, 1000mg in supplements is more than enough. Any more than that and you’re risking getting urea stones etc.
Protein is what the muscle is actually made of. When you excersise it is broken down. Obviously more (lots more) is needed to repair the muscle. I think growth occurs when the body overcompensates and builds more muscle so that it won’t get damaged as much next time.