Under the hood there is a pipe that is broken from the blower motor

To the left of the engine, what is the part that is connected to it that i need to replace? It is to the left of the engine, close to the edge of where the hood is. the pipe comes out of some part i don't know makes a sort of U-Turn and connects to a metal wall of some sort. the coolant container is empty if that helps but i don't know if that is because i never changed it or because of the hole in the pipe. the truck runs but not as well as it should.