Headless Mode in Craft CMS
An overview of how the new headless mode works in Craft 3.3 and later.
More you should learn about Craft CMS:
Craft CMS 4 Feature: Element Auto-Refresh
Craft CMS 4 Feature: Condition Builder
CraftQuest on Call 44: The Most Important Craft 4 Features
Craft 4 Upgrade Utility
Craft CMS Quick-Start Guide
CraftQuest on Call 43: Inside CraftQuest
When should I use multi-site in Craft CMS?
CraftQuest on Call 42: Upgrading to Craft 4 Live