Can airplane stop while flying

It can if the aircraft you're on is a helicopter! Further, a plane can theoretically have zero ground speed if the headwind it's flying into is great enough to support lift and the aircraft doesn't have enough power to overcome the wind. This is somewhat counterintuitive, but imagine you were in a boat instead of a plane. If your boat can manage only five knots in perfectly still water, then it will go zero knots if you're trying to sail upstream in a five-knot current. You will make no headway. It's the same with a plane.