I have a nozzle for an air flow and I need to create a 90 degree “elbow” for it to redirect the airflow 90 degrees. How do I do that? Thanks!
You can sketch a circle and a line outside the circle and then revolve the circle 90 degrees around that line.
Did you check out the Sweep tool? The example video in the manual behind the link in fact shows a 90 degree elbow for piping 
If that’s different from your use case, a quick hand-drawn sketch would help a lot.
Sweep would be my choice for a simple elbow.
As you can see, there’s more than one way to skin a cat…er, create an elbow. Sweeps are necessary when the path is not circular.