Lightroom refers to the location from where those images were originally imported.
Choose any image or folder > right click/command click > choose Show in Finder/File Explorer > this will take you to the location where that particular image is stored on your hard drive.
Photos are on your hard disk somewhere, wherever you put them, or wherever you instructed Lightroom to put them. You can find out exactly which folder the photos are stored in by right-clicking on the photo and selecting either "Show in Finder" or "Show in Explorer" (both of these open your operating system window showing where the photo is stored) or "Go To Folder In Library" (which shows you which folder the photo is in over on the left in the Lightroom Folder Panel).
If you need to get a grip on organization, then please strongly consider organizing by keywords and other metadata which describe the content of the photo, instead of trying to remember which folder your 27,000 photos are stored in. Assign keywords and other metadata to each photo to describe the content (for example, "beach", "waterfall", "Thanksgiving", "Cousin Bob", etc.). It's a lot easier to remember the content of a photo than to remember which folder it is in. Once you have the keywords and other metadata assigned, it is very easy in Lightroom to search for all waterfall photos, or all photos of Cousin Bob, or all photos of Cousin Bob taken at Thanksgiving, etc. (This is much more difficult or impossible to do if you organize by folders).
Yes, adding keywords and other metadata is actual work, it takes time and effort and thought, but I'm sure you've heard the old saying: "The benefit is proportional to the effort you put in". I will never go back to folder organizing, it simply doesn't get the job done for me. I still put photos into folders by capture date, but I don't try to remember what folder the photos are in (I couldn't possibly remember the folder location of 27k photos even if I tried), and I don't use folders to find my photos, I use keywords and other metadata.