By the way, if you're in a situation where you want the vast majority of files/folders in a given location selected, but need to leave a few out, you can do this process "in reverse" as well
Hit CTRL+A to Select ALL
Hold down the CTRL Key, keeping it held, and up/down arrow to the individual files/folders you don't want and hit Spacebar when you're on them to deselect
Release the CTRL Key
It can be a lot less tedious when you want most, but not all, than selecting them one by one with CTRL held down.
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
~ H.L. Mencken, AKA The Sage of Baltimore