I'm surprised nobody has mentioned this before now, but if you go on the my.scouting training portal, there is a training unit and video, as I recall about 10 minutes long, specifically showing how a PLC is run by the SPL with the Scoutmaster to the side observing or asking questions. I happened to notice it when renewing my YPT last year and watched it, and it was actually pretty good.
I just double checked it's called "Patrol Leaders Council Meeting SCO-477."
There are a bunch of related videos on Patrol Method, boy-led, etc. Definitely something a new Scoutmaster crossing over f