This is a hands-on training on Linux commands and Bash scripting, with lots of step-by-step examples, and with concise (not very detailed) explanations. To get the maximum benefit from it, you should try these commands and examples yourself, rather than reading or just skimming through.
These examples are mostly based on the wonderful book The Linux Command Line by William Shotts. So, for more detailed and complete explanations, and for a deeper understanding, I recommend downloading and reading the PDF version of this book. I cannot recommend it highly enough.
You need a Linux terminal to try these examples. I would recommend using a virtual machine or a container with Ubuntu or Debian.
If you already use Linux on your personal machine (laptop), it is still NOT recommended to try the examples directly on it. They are are not harmful, but a mistyping or some other mistake might have unexpected results.
There are lots of ways for running a virtual machine. Using a podman container is one of the simplest ones.
These lessons have been used previously on this online course. The video recordings for the scripting part are published on YouTube:
There is also an italian version of these lessons, translated by Claudio Cavalli.
A PDF version of these lessons is also available for download.