Dedicate a set amount of time when you only use the cli to accomplish things. Pick simple, low risk things like cleaning up unneeded downloads in your downloads directory. Start with one file then try wildcards, brace expansion and regex.

View logs and grep to find specific events. Investigate (read only) what type of data is provided under different directories under /.

Use online resources to learn a scripting language, bash is convenient to start with, as it’s a common default shell and can be used for scripting. Learning bash can translate to one liners and eventually scripts.

This is a good resource, but I would recommend to not read it like a book, but maybe investigate sections of interest after you get a feel for some of the early topics: https://tldp.org/LDP/Bash-Beginners-Guide/html/

Lots of people are suggesting using TUI applications.

While I don’t disagree that will make you more comfortable spending time in the terminal, you’re not really getting better at the command line (CLI).

I recommend you learn the basics of how the shell works. This is a good resource: https://effective-shell.com/

Switch to Gentoo. Either your command-line abilities will improve, or you will run screaming into the night before you manage to get X (or Wayland) up and running. 😜

Someone already mentioned The art of command-line. It’s a start.

And just use it… you’ll get better at it with time and practice.

Also, make sure your use of the CLI enhances your workflow, or it won’t work.

Start to use command line tools like mutt, links and so on. Okay, maybe not links, but mutt is still the best MUA around.

And whenever you are asked to get some data out of an excel sheet, export it to csv and use sed, awk, grep, wc, cut, uniq, sort, head, tail and stuff.

No, stuff is not a command afaik 😁

Force yourself to use it. Find the things you do everyday and research how to do them in the terminal