WIP See: Blog re: primitiveone https://primitivedigital.uk/blog/primitiveone/
WP Dev Docs: https://developer.wordpress.org/themes/advanced-topics/child-themes/
Basic files http://wpamanuke.com/how-to-create-twenty-twenty-child-theme/
2020 breakdown: https://kinsta.com/blog/twenty-twenty-theme/
File examples https://github.com/primitiveshaun/wp_theme_basetheme (old) https://github.com/carlodaniele/twentytwenty-child