Does it pull the air from outside, or push it from the engine bay to the outside?

 

Any fan for cooling is designed to pass air thru the radiator and onto the engine.
You can have a pusher that mounts on the outside of the radiator that pushes air thru the radiator or you can get a puller that pulls air thru the radiator onto the engine.
Pullers seem to be the most popular, I've never seen anyone run a pusher, course I'm only 22 and relatively new to cars, I'm sure some of the old timers have seen them

 

it sucks air through the rad, pushing it towards the motor.