It takes some time to understand the manpage format but it’s worth the time because they’re always available.

When I first started, I used the website explainshell to help my get an idea of how the most common commands worked.

This has the benefit of referencing the man pages directly so you can better learn how to interpret them.

apropos foo

compgen -back

In another comment, OP said they checked the arch wiki, specifically https://wiki.archlinux.org/title/File_recovery. The arch wiki is a great resource; most of the information is not arch-specific and is useful for linux in general.

Regarding “let’s try sudo”: you should get familiar with sudo because it’s one of the most important linux commands. It runs a command with elevated privileges (it originally stood for “super-user do”). That means sudo isn’t actually the important part of the commands; it just means that the following commands (pacman and photorec) need elevated privileges. pacman deals with systemwide package management and photorec needs access to the raw storage device objects in order to recover files.

In the old days, we would ls /usr/bin/ (sic, there are several locations defined for apps) and either look at the man page (if it existed) for the items we saw, or just run the commands with a --help option to figure out what they did. At best we maybe had an O’Reilly book (the ones with animals on the covers) or friends to ask. You can still do that today instead of reading blog posts or websites, just look, be curious and be willing to break something by accident. :)

Part of the Linux journey is to be inquisitive and break some stuff so you can learn to fix it - unlike say Windows, on a Unix-style system the filesystem is laid out in a very specific way (there’s a specification [1]) so one always know where “things” are - docs go here, icons go there, programs go here, configs go there… - lending itself to just poking around and seeing what something does when you run it.

After awhile your brain adjusts and starts to see all the beautiful patterns in design of the typical Linux OS/distro because it’s all laid out in a logical manner and documented how it’s supposed to work if you play the game correctly.

[1] https://refspecs.linuxfoundation.org/fhs.shtml

A very nice terminal-based cheatsheet is named tldr (or tealdeer).
It gives you a very short explanation of what a program does, and then lists common uses of that program and explains them

I’ll be real with you. What you need to do is, whenever faced with a task that sounds like it needs CLI, go search stackoverflow for that task. It probably has something slightly relevant to what you need, you take the commands from that answer and read their manuals.

there are lots of cheatsheets out there but the best way to learn commands is practice. different people will use different commands, so you may not need to spend time learning ffmpeg syntax whereas others find it invaluable. Google is your friend while learning. if you have a Linux question, chances are someone else has had the same question and posted about it online. as far as basics go, spend some time learning about grep and find, they are probably the two most valuable basic commands imo outside of the common ls/mkdir/etc.

as for sudo, it’s just “superuser do” so it’s essentially the same as hitting run as admin in windows. lots of times if you try to run a command without sudo that needs it, you’ll get a permission error which reminds you to run as superuser. it eventually becomes second nature to say “ah, this command needs direct access to a hardware device or system files” which means it’ll need to be run with sudo.

Becoming familiar with the essentials, grep, awk, sed is a good start. Manual pages can of course be accessed using man followed by the command/program you want to know more about. Understanding operators like |, >, >>, etc. can help as well. And reading the entirety of man bash is a good way to dive in further.

I am also a novice so take that into account. But it seems to me it’s something you learn over time what commands do what and when to use them. I think it’s kind of like knowing what folders or settings to navigate to in other operating systems. Over time you get a feel for it.

Also most troubleshooting guides or things like photo rec have the steps kind of built in and explained to you what commands do what.

If the guide you’re reading has the steps try to break them down and figure out what the command is actually doing rather than blindly copy pasting.

Most of what I’ve learned has been the handful that have stuck when I’ve looked up how to do stuff. If you ever install a minimal distro and follow a guide or anything that’s a great way to learn. Or if you look up how to fix something and you find commands on the internet, you can look up what their solutions do. But mostly I’m just replying to wish you well on your journey.

Best of luck with linux, hope you have a lovely day ☺️

AI is great for learning Linux imo, e.g. ask “why did my command say Permission Denied?”. If you object to ChatGPT there are local AI engines too