It'll probably be a while until he joins a House, I'd leave that bit for him to find out later, at his pace.
For now, the three guilds on Balmora should have quests to get you started on the world.
Stamina affects everything, so if you run out of stamina in combat stall for a bit until it's at least half-full again.
Another important combat bit are the weapon damage ranges. Hover the cursor over them at the inventory to check which attacking movement is better for your chosen weapon.
Walk forwards or backwards and hold attack button = thrust
Walk sideways and hold attack button = slash
Stay put and hold attack button = chop
For example, axes cause pitiful damage with thrusting, but great with chopping and slashing. This means that when fighting with an axe, you'll want to move to the left or right (or stay put), hold down the attack button for a while and then attack. Don't attack while marching towards the enemy or you'll stab him with a weapon that sucks at stabbing.
Since you use daggers, you probably noticed they have a high minimum damage, but the maximum damage isn't much higher than that. This makes them good for fast stabbing motions. So you'll want to close in, stab a few times, then fall back to recover stamina. If you chose the premade Agent class, you have Conjuration as one of your major skills and started with the Bound Dagger spell. It summons the best dagger in the game, complete with an enchantment that ups your hit rate. Use it often.
If you don't have Bound Dagger, one merchant in Balmora sells short swords that let you cast it.
this man.
