Is car a noun?
“Car” is the noun (a thing, person, place, state, quality, action, or concept.) What type of word is girl? A young female (in contrast to boy), usually a child or adolescent.
Is it “in the car” or “on the car?
Both “In the car” and “On the car” are grammatically correct, but mean different things. “In the car” should be used when talking about something within a car, such as a passenger. “On the car” refers to something that is on top of the car, such as luggage. The preposition “In” is used to refer to being on the inside of something.