I like the Linux upskill challenge for rounding out your education. https://linuxupskillchallenge.org/ it’s designed as a 1 month course of an hour or so a day that the author made free to access as his legacy. Don’t start out with this – mess around and learn on your own first, and when you’re comfortable with the system, then you can learn more in depth.

I recommend spending time in a Linux chat room related to learning Linux specifically your distro. When you’re messing around in Linux, you can ask questions, and humans are great teachers in helping you with things you don’t know you should be learning. Discord is the most accessible, but you can find a specific place for the Linux distribution you go with – for example Ubuntu has rooms set up on Matrix and IRC that are both active and welcoming to new folks.

Also just dive into guides on how to do things as you need to do them. How to change wallpaper, how to install programs, whatever. Try finding official documentation, but often guides may be more helpful. But sometimes less. Over time you will learn how to search for answers just like on Windows. If the guides or forum threads don’t seem right, you can ask in the chatroom (hey does this make sense?)

Compared to cmd.exe and Powershell, the Linux terminal is very user friendly, with a user experience they’ve been refining since the 1970s or earlier, and there is a reason power users tend to gravitate towards using the CLI for some tasks. Sometimes it may be the preferred or only way to accomplish something (Windows has this too, but it’s more rare.) Take your time, and read/understand the man pages and the output of nano --help (using nano as an example command: it is a text editor. But you can use the --help option with nearly any Linux command and it will most likely work, by convention.

Sorry if any of this is too obvious or too much information, but hopefully it helps someone.