Is there any reliable, repeatable way to find a folder on MacOS? I have a folder full of Logic projects on my local drive. Finder offers no way to get to it. It's a constant frustration. I can get to iCloud, Downloads, Applications -- but not my own files on my own disk drive. 

I understand that Apple has strict usability standards, and I respect that, but is there any way to work around them and conveniently access my own files only own computer, other than a keyboard shortcut that I'll forget and have to Google every time? (It doesn't work anyway -- the first time I tried, there was no folder named "Logic" in whatever unknowable scope it's searching in; the second time I told it to open "Logic", it opened Downloads. I can take a joke as well as the next guy, but sometimes I just want to get to my files). 

Is it possible to create a link to a folder on the desktop, or something functionally similar? Something I can easily find when I want it, and click on it? 

To clarify: I'm coming at this from a Windows/UNIX based expectation that all the folders are in a unified tree that's rooted somewhere, and you use one application (bash, DOS prompt, Windows Explorer, whatever) to navigate that whole tree: Some branches of the tree are on the local disk and "real", others are "virtual", but they all have a chain of parents starting at the same root. 

But I'm starting to think I may need to learn a different way of thinking about this stuff in order to use MacOS. 

The actual problem I have here is: I shared three Logic projects via iCloud with a pianist. We recorded many takes of his parts at his apartment. Then I needed to copy the projects from iCloud back to my local disk. "Open three projects in Logic and Save As for each one" is a very slow and awkward way to copy three files from one folder to another (or archive, or whatever a "single file" Logic project actually is).
https://support.apple.com/kb/PH13433?locale=en_US explains better about file save location for the app. If you're doubtful, open Logic, try to Save a new project and remember the location.
Replying to your: "whatever unknowable scope it's searching in", there are two places where it is written that "This Mac" is being searched. So see there to find the scope.





You can add the folder Logic(if and when you find it) to the sidebar by dragging the folder to the Favourites. 
You can go to Finder Preferences and set the folder under General -> "New Finder window shows" as your folder Logic. But you'd have to open a new window for that, so remember that shortcut as per File Menu in Finder.