My first KiCad decision was that I will use only my own libraries and just created all of them as my first task before starting a first PCB. But I was doing it with KiCad V4 and things changed on the way from V4 to V8 so I don’t know how to do it now, but you certainly can use your libraries.
Once upon a time someone asked about KiCad directories organization and what I have written may be will be of any use for you so here it is:
I don’t know how to do it now as ways of doing it have changed