You want to get a little underpowered dirt bike to learn on, you tend to abuse the clutch, head bearings, chain and forks a bit when you're learning, I know I did!
..or instead of a dirt bike.. a nice 50cc scooter... (just to understand the right point and not to be scared of flipping over.. as the rear brake on a scooter is on your left hand and not on your right foot!!) Picture made last week in Italy going home from the bar...