If you stick with it you’ll eventually start to understand what all the jargon means.
sudo is kind of like “run as admin” in windows. It runs whatever command as root(admin) instead of as your user. To use it you just add sudo in front of the command. Ex. “apt-get update” becomes “sudo apt-get update”
apt-get is the command that controls your Ubuntu Repository. “apt-get update” basically checks for updates for everything on your computer. Then “apt-get upgrade” downloads and installs all those updates. And “apt-get install <app/package name>” is how you install apps that are in your distros Repository.
A Repository is basically an app store for your distribution. Each Linux distribution usually has their own. And they have different software(apps) available in them. If a app you want is not in your repo there are different options to install it. That was probably the hardest part for me to understand when I started. But now days the easiest option is to use snap or flatpak to install something that’s not in your distros Repository.
As far as I understand, a package is just another way of saying app or software program. There might be a technical difference. But when you download a package you’re basically just downloading the program/software/app.
There are also package dependencies which is the other software that is required to run the software you’re trying to install. When you run “sudo apt-get install <package name>”. You will see a list of packages that will be installed. This includes all the dependency packages. Which are the packages that are needed to run the one that you’re trying to install.
Some linux distribution try to give you a GUI for everything. But its definitely worth learning how to do stuff in the terminal. Once you learn it you’ll realize why it is so much better than a GUI.