You're reading the documentation for an older, but still supported, version of ROS 2. For information on the latest version, please have a look at Galactic.
Many of the tf2 tutorials are available for both C++ and Python. The tutorials are streamlined to complete either the C++ track or the Python track. If you want to learn both C++ and Python, you should go through the tutorials once for C++ and once for Python.
If you have not yet created a workspace in which to complete the tutorials, follow this tutorial.
This tutorial will give you a good idea of what tf2 can do for you. It shows off some of the tf2 power in a multi-robot example using turtlesim. This also introduces using
This tutorial teaches you how to broadcast static coordinate frames to tf2.
This tutorial teaches you how to broadcast the state of a robot to tf2.
This tutorial teaches you how to use tf2 to get access to frame transformations.
This tutorial teaches you how to add an extra fixed frame to tf2.
This tutorial teaches you to use the timeout in
lookup_transformfunction to wait for a transform to be available on the tf2 tree.
This tutorial teaches you about advanced time travel features of tf2.