I cannot find my Photos Library when trying to import into Lightroom Classic, and I don't know where else to look. Macintosh HD - Users - iMac - Pictures is how I can get to it on my computer, but when I try that from the sidebar on the LRC import screen, my Photos Library isn't there. Have I missed a step somewhere? Thank you!
Lightroom Classic cannot import an Apple Photos library, only the older iPhoto and/or Aperture libraries. To import photos from Apple Photos you'll have to use 'Export Unmodified Original' from Photos. That will save the photos in a normal folder.