I'm new to LRC, so here is a basic question. Importing photos from a dedicated folderstructure on my PC into LRC works fine. But if i add photos to a new folder in the strtucture on my PC and i want to synchronize them, the reslting interface to start synching shows "Import new photos (0)"
If these photos you add have already been imported into Lightroom Classic, then this is the expected behavior ... Lightroom Classic will not import them again. This is a good thing, as you do not want a photo imported twice into Lightroom Classic.
Instead of moving photos from folder to folder (as you seem to be doing), a better way to organize in my opinion, is to assign keywords and other metadata, and leave the files where they are.