Airplanes use a mixture of science, construction of the wing, and the engine to generate lift. But how does science, architecture, and materials result in finding out how airplanes get lift?
First of all, the science portion of of the wing. The wing uses a scientific principle called Bernoulli's law of fluid motion. This states that as a fluid passes a distance at 2 points the speed changes, fluids flow from high to low. For example imagine the airplane wing. The wing is flat on the bottom and curved at the top. As the air on the bottom part passes, it goes at a slower speed then the top portion. This is because the top portion has to travel even further because of the bend but at the same time, meaning faster speeds. And since fluids tend to flow from high to low, the wing goes up. Another example in an everyday aspect of life is drinks. If u drink a soda with a straw at a restaurant, you are applying Bernoulli's law to drink it. You provide a low air pressure in your mouth when you suck in the straw. There's a negative air pressure in there and the low pressure in the soda forces the soda up the straw. So overall, science uses Bernoulli's law of fluids moving from high to low to create lift.
The second variable that makes an airplane generate lift is the design of the wing. The wing is specifically designed to use Bernoulli's law to it's full extent. As stated before, The wing is flat on the bottom and curved on the top. This means as the wing cuts through the air, the bottom part of the wing has a smaller distance to travel. And the top part has a further distance, this means the fluid is going faster and the particles are less packed up.
The wing has to follow these rules to achieve lift as well. You cannot have a flat wing and expect to fly.
And finally the most obvious reason how an airplane generates lift is the engine. The engine is a complex part of the airplane that speeds up air before it passes the wing. It speeds it up and gives it a kick start before the airplane starts. Sort of like an alternator turning on an engine in a car to start it up. It's the same concept but used in aviation rather then driving.
So that is how an airplane achieves lift. It applies knowledge of science laws, architectural intelligence, and modern technology. And now you see what the requirements of achieving lift is. So if anyone ever ask you how an airplane flies, you can answer them with this long explanation. And spread the knowledge around. On a side note, paper airplanes do not generate lift as some would expect. They are just simply well designed crafts that gently glide down at slow speeds making them look like they fly.