For Myc: You mentioned running scripts so I figure you are up for copy and paste in to the terminal ....
20 Things to do After Installing Ubuntu 18.04 and 18.10
Have you opened up the application "Terminal" before? I believe they give options for doing these tweaks through the Software Centre as well to avoid the terminal if its to much...
Regarding not seeing an off-button... the newest versions of Ubuntu use a unique desktop that doesn't really use traditional toolbars as we know them. There is a lot of right clicking and setting up the menu on the left (it's moveable). There are many custumizations as I mentioned. Have a play around and see how you like the menu system as is , get to know it etc. If you prefer "old-school" toolbars you can install those Gnome extensions within your current Ubuntu setup. It's pretty easy. If you change your mind you can switch back.
You see in there that there are also things called themes which make the look and feel of your desktop different (I prefer dark windows / menus)
Edited by hyphaenation, 11 July 2019 - 12:49 PM.