Copes F The Linux Commands Handbook 2020

Textbook in PDF format

The Linux Commands Handbook follows the 80/20 rule: learn in 20% of the time the 80% of a topic.
This book does not try to cover everything under the sun related to Linux and its commands. It focuses on the small core commands that you will use 80% or 90% of the time, trying to simplify the usage of the more complex ones.
All those commands work on Linux, macOS, WSL, and anywhere you have a UNIX environment