https://docs.kicad.org/7.0/es/pcbnew/pcbnew.pdf
Tutorials
https://github.com/Bouni/kicad-jlcpcb-tools
add this repo to the kicad manager:
<https://raw.githubusercontent.com/Bouni/bouni-kicad-repository/main/repository.json>
ebastler repo - lots of keyboard parts and such
<https://raw.githubusercontent.com/ebastler/ebastler-KiCad-repository/main/repository.json>
prety much everything else is in the plugin and content manager by default.
https://techexplorations.com/guides/kicad/3e/kicad-paths-and-libraries/