the following is assuming that ros2 has already been downloaded

Basic terminal commands

ROS2 workspace basics

Sourcing Environment Setup Files

ROS2 Communication Basics

Recording in ROS2

Making Workspace

Making Package

✅ Rule of thumb :

If you do the action below this actions should be followed up
Edit code colcon build
New terminal source again (overlay source (default ROS2) + underlay source (workspace))