After you copied the photo folders, and the catalog support folders, and the catalog to the new drive, you opened the catalog on the new drive, right? (Looks like you opened a new empty catalog.)
After you open the correct catalog, in the Folders panel, do a "Find missing" on the top-most folders so that you can tell Lightroom where all the folders now reside. (Lightroom knows the difference between a missing file and a file in a missing folder; you need to fix the missing folders first.) Lightroom will autofix all the folders under the top folder you relocate.
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