Why are F1 cars designed to be the shape they are?
F1 cars are designed with the smallest possible frontal area
(where the drivers legs go) to minimise drag (friction).
Their length, track, and wing dimensions are defined by the regulations governing F1.
The wings, spoilers and general shape, even the underbody are all designed with aerodynamics, downforce and streamlining in mind. The car needs to pass through the air as quickly as possible, gaining as many benefits from it as possible.
The holes in both sides of the car and above the drivers head
(shown in the picture above!)
all allow cold air to filter into the car to cool the engine.