The lift of an airplane is similar to that of a balloon. It uses the density difference of air, right? The air density on the top surface of the balloon is low and the air pressure is small. The air density on the bottom surface of the balloon is high and the air pressure is large, which produces an upward force. If the weight of the balloon is less than this force, the balloon will rise. Due to the movement of the wing, the air density on the top surface of the wing is low, the air pressure is small, and the air density and air pressure on the bottom surface of the wing are high, which produces an upward force. If the weight of the aircraft is less than this force, the aircraft will rise. Right?
It uses the density difference of air, right?
No, it doesn't. At least for slower speeds (not approaching transsonic), we can treat the air as an incompressible fluid. The dynamic pressure changes from point to point, but the density of any parcel of air is approximately constant.
Yes, both buoyant and aerodynamic lift require there to be a pressure difference between the top and the bottom of the lifting body. But balloons exploit the pressure gradient already in the atmosphere, while wings create a pressure difference based on dynamic air movement.
It is not correct to point to density differences as important for subsonic wing operation.