What you've described is parasite drag. Think of it this way, you have to move very few air molecules out of the way to push a bullet through the air. Many more molecules have to be pushed aside to move a house through the air. Parasite drag is broken down into some parts, friction drag caused by the air flowing over the skin of the aircraft , interference drag caused by air flow meeting as it passes over different parts of the aircraft (say over the top of the wing and along the side of the fuselage and form drag, just pushing the shape through the air.

Yeah, they talk about induced drag being caused by the vortices wrapping around the wing tip. What you need to know is that induced drag is caused by creating lift and increases as the aircraft slows down. Parasite drag is caused by moving through the air and increases as you speed up. Where the two lines cross is your best L over D.

And you wonder why people say you should get your CFI.