Once you have done the initial setup all focussing and guiding is driven from the front end app (Kstars).
You can run Kstars either from a remote system or directly on the Pi.
I let INDI run on the Pi and run Kstars from a laptop. If you are using this setup make sure connection between your laptop/PC and the Pi is a strong one. You do not want to be loosing connections or have a slow connection. A slow connection is a real killer for Focus and Guiding. I guess you could run Kstars on the the Pi for Focus and Guiding but that is a little too complex for me.