Answer:
There are different forces (pushes and pulls) that make flight possible.
Lift is caused by the variation in air pressure when air flows under and over an airplane’s wings. This force lifts up. It is opposed by weight, or the force of gravity, pulling downward.
Thrust is caused by the action of the propellers moving the plane forward. Opposed to that is drag, caused by air resistance. If lift is more than weight, the plane will rise. If thrust is more than drag, the plane will gain speed.
Airplane wings are designed to take advantage of lift. They are shaped so that air has to travel farther over the top of the wing than underneath it.
When the air has to travel farther over the top of the airplane wing, it must also travel faster, which results in lower pressure. The shorter distance under the wings results in higher pressure, causing the airplane to move upward.