Assuming it’s not too late: Painbow’s build is pretty good for a new player that wants to provide some protection for his friends. I said “provide protection”, not “tank”, as there is no tanking in this game…and you will literally be applying the Protection boon (buff) all the time, heh. It’s pretty durable build, and doesn’t lack in damage, either.
It uses Hammer as primary weapon, and I support CYB’s recommendation of Mace+Shield as secondary, as a defensive setup. For your gear, mix Knight’s with Berserker’s/Valkyrie gear and trinkets, and you’re good to go.