Which hand do you use? Left or Right?
Both.
Seriously, you can't single out a hand which a person uses all the time.
Besides, they vary on what the task at hand is, and on the situation.
I'll tell this much that I'm only good at writing with my right hand.
Even at drawing, I'm only mostly good with the right hand, and use the left hand only when I need a special form of colouring method.
I use my left hand to do washroom works... lol!
Other than these three things, I'm pretty much totally ambidextrous.
I'm equally good at using both hands at almost eveything, and therefore use them to equally to carry things around, to type, to attack with, to lift weight, to play instruments, even to eat(I eat with spoon), to block, to armwrestle, while steering, and for sooo many tasks that exists.