tagged photos without keywords

I now have tagged photos without keywords.

?? "Tags" are Keywords. Add a Keyword to a photo- it is tagged. Tag a photo- it has a keyword.

Apparently, the photos were tagged after finding the duplicates.

Yes. Teekesselchen will provide two results-

1) Photos it 'thinks' might be duplicates are 'Tagged' with the Keyword "Duplicate"

2) A Smart Collection is created ("Duplicates") that will, if selected, show all the files that have been Keyworded 'Tagged' with the "Duplicate" keyword.

Now, however, I won't be able to find those photos using keywords.

You will- as long as you do NOT remove the Tag/Keyword from the photos. Either-

1) Click on the white arrow at the end of the "Duplicate"keyword. Or-

2) Click on the Smart Collection "Duplicates".

However, Teekesselchen can only SUGGEST to you the files it believes to be 'Duplicates'. YOU have to make the decisions of which files you may want to delete. You may have different edited versions you must keep.

Is this a question about Lightroom Classic?

If so, what does this mean?

I now have tagged photos without keywords.