Practical applications of midi?

Complete midi noob here. Never used it, but curious to dabble.

I noticed that the QC has midi in/out. I also have some chase bliss pedals with Midi, and a Microcosm which has midi. These extra pedals are in the FX loop of my QC.

So I am wondering- what’s the best way to use midi in this context?

Should I be running midi into the QC and other pedals and using a 3rd party midi controller to recall presets/scenes/midi switch?

Can I just run the QC midi output into the other pedals and have them switch setting based on different scenes?

What’s a midi clock and how does that play into the QC?

I also wouldn’t mind picking up something like a beat buddy and using that with the QC for solo practice… it also has midi?