if you want to control the pyramid you will need something that can be configured to send particular CC - you should also familirise yourself with pyramidi, as this determines what you control on the pyramid … its a good set, but its far from everything.
enterings notes, anything will work.
beyond this you can also assigned CCs to particular midi fx.
you will need a controller that has midi din (or a midi trs + adapter to din)
something that quickly switch between midi channels is very useful too.
not quite sure what you mean by this…
the pyramid will respond to note on/off - so will reflect what you play on the keyboard.
you can also assign notes to the things like smart chords and master transpose.
see : https://squarp.net/pyramid/manual/settings#ancre02
i think above all, the question here is what are you trying to achieve.
personally, I just use a keyboard (for note entry) , beyond that I tend to just use the Pyramid itself - as i find the UI very good on it.