So I’m quite the new user in a way myself, I started out using the Slackware distro in my youth, and now 15+ years later, I still have some problems remembering the basic stuff. I didn’t find a direct topic for this, so I thought why not make one for the new users out there. I will be adding commands in this post from time to time.
su / sudo
Su is the precursor to the Sudo command, while sudo is used in order to borrow root access, su is instead direct root access, this is what was used for Slackware, and should not really be used at all for the beginner, this is from my perspective and knowledge why Sudo was introduced, in order to be more secure. Instead of becoming root, you instead borrow root access.
https://www.tecmint.com/10-lsof-command-examples-in-linux/
https://www.tecmint.com/dpkg-command-examples/
https://linuxconfig.org/howto-mount-usb-drive-in-linux
https://docs.kde.org/trunk5/en/applications/fundamentals/kbd.html