restoring the catalogue after update from Win10 to Win11

Hello

I saw an earlier post with this question, but it seemed the user didn't get an exact answer, at least not that I could see.

I am using photoshop elements 2021.

I recently took my computer into the shop for them to do a "clean" install of windows 11.  Before I took it in, I backed up the catalogue.  (I also separately backed up the "pictures" directory.)  Surprisingly to me,  when I got the computer back, the shop had backed up and re-installed my files, so all the pictures are still there.

I just re-installed photoshop elements.  If I restore the catalgoue, will I end up with two copies of each photo?  Should I  delete the photos that are there and then restore the catalogue?  (I have a back uo of all the photos so I'm not worried about losing them.)   

Elements has given me the option of importing all the photos on the drive, and I briefly thought about doing that, but then I'd have to re-do the cataloging - almost 55,000 photos going back to 2008!! - so not doing that!

Thanks