Best course to learn more about the Linux terminal?

[pickled-potato]

What is the best course in your opinion to learn how to use the terminal (Ubuntu specifically)?

[again?]

There is one here that is very good for beginners.
https://ryanstutorials.net/linuxtutorial/

Also a bash scripting tutorial. https://ryanstutorials.net/bash-scripting-tutorial/

Most commands you come across will have a manual page for further options.
eg

man ls

and/or
bookmark Ubuntu's online manual pages. http://manpages.ubuntu.com/

[TheFu]

What is the best course in your opinion to learn how to use the terminal (Ubuntu specifically)?

Forget about an Ubuntu-specific course. Any Unix course is fine. 90% of Unix is the same as Linux is the same as Ubuntu.
Which course will work best for any person depends on so many personal considerations that it is impossible to suggest anything except areas to research. The way an end-user should learn the shell isn't the same as a programmer or an admin would learn it. They all need that 1st 2-week class (1 semester course), but after that, programmers will head off into scripting quickly. Admins will move into DevOps, automation and security, while end users will probably stop.

If you learn best in a classroom, take the Unix course from your local community college. This method also helps people who aren't self-starters, because there are 2x a week deadlines for learning material. Community colleges are relatively cheap - usually less than $200 per course, per semester.

If you want a condensed course and have lots-o-money, there are local technical training centers that will teach basic Unix shell stuff in 1-2 weeks for $1200-$3000. The problem with this method is that time doesn't allow the material to be digested, so it becomes memorized for the test, not "understood" so it can be built on over the next few years. My job sent me to this sort of training many years ago.

If you are a self-starter, find a book, and work through it. http://linuxcommand.org/tlcl.php LPI has some too.

I'm not a fan of any online courses, though the EdX courses are free and taught by reputable University professors from top schools.

I won't PAY a place for any Linux courses until after you are passed the 1st 3 levels - getting into intermediate administration stuff. Only then would I consider paying for more specialized training like Amazon EC2 or AWS or Azure or Kubernetes or whatever the Serverless or Container or Virtualization new "hotness" is that week.

If you need a course on Apache, then you need to find a different career.
If you need a course on DBMS, then you haven't spent enough time on youtube watching {insert DBMS} videos which cover clustering, HA, replication, DR, performance and recovery techniques.

Some people need to spend money to force themselves to pay attention and learn. If that is you, just know that the free resources are at least as good as the paid ones. Pay if you must, but with your eyes open.

[pickled-potato]

Thank you, both of these responses are very helpful!