Drupal.org (aka: dee-dot-oh)
https://www.drupal.org/
The Drupal project’s official website.
Planet Drupal
https://www.drupal.org/planet
Planet Drupal aggregates blog posts from the Drupal community. It is often a great source of information. There is a Planet Drupal RSS feed for those still using RSS readers.
Drupal 9: Selecting Machine Names For Content Entities And Fields
#! code
https://www.hashbangcode.com/article/drupal-9-selecting-machine-names-content-entities-and-fields
Drupal 9: Loading All Routes From A Module
#! code
https://www.hashbangcode.com/article/drupal-9-loading-all-routes-module