I’m trying to install a 7001 routing valve what are the inputs and outputs?

This will change depending on how you’re using it. You will either have two inputs and one output or one input and two outputs. The most common use is to select between city and bottled water. For this application, the center barb will be your output. The barb closest to the toggle will be one input and the barb farthest away from the toggle will be another input.