All cars will creep forward with the first gear on. The thing is, if you're already going faster than 10km/h, they'll decelerate towards that surprisingly quickly.
Not really. On petrol cars, if you let go of the clutch in 1st gear and not pushing on the gas, you'll most likely stall. Diesels often don't do this, and creep instead (all of this assuming you're letting go of the clutch slowly enough, otherwise, you'll stall for sure)
It depends on the condition of the clutch. If it’s a newer clutch or in great shape: definitely not once the gear is fully engaged. I can’t drive my petrol cars in forward or reverse at driveway speeds without riding the clutch a bit to stop from going too fast.