Linux Journey
An interactive, structured free learning path from basics to advanced Linux command‑line topics, organized into modules like Command Line, Text‑Fu, Networking, and more.
LinuxCommand.org
Learn the power of the Linux shell—commands, scripting basics, tutorials and book recommendations—free and beginner‑friendly.
Linux Survival
Free interactive online Linux tutorial with a browser‑based console simulator to practise essential commands in real time.
Ryan’s Tutorials – Linux Command Line
https://ryanstutorials.net/linuxtutorial/
A clear and practical 13‑part beginner's tutorial covering Bash basics, file navigation, command usage, and shortcuts.
TLDR Pages
Community‑driven simplified man pages for common Linux utilities—short, friendly examples for command‑line help.
LinuxQuestions.org
One of the most active free Linux forums—ask questions, browse threads and learn from a large community of users.