Hey Victoria Herring!
Is this an M1 Mac?
Does this happen for data in other locations than Desktop and Documents? Likewise, is other iCloud data syncing fine? And finally, does it matter what network you’re connected to? If you’ve already tested all that, and given iCloud Drive enough time to do its thing relevant to the amount of files it’s supporting, try this, (From my own experience in this matter):
In the hopes of saving you some time and energy, (Which I’ve spent much on this). If you have your data backed up already, and especially if your iCloud Drive data hasn’t fully downloaded to this Mac yet, but is in iCloud, try this:
Move this folder “CloudDocs” to the Desktop (Just as a backup). Restart the Mac, wait for the data to start downloading.
~/Library/Application Support/CloudDocs
Hopefully that does it!
To get there if you’re not sure, open Finder.
While holding Option on your keyboard click Go.
Then click Library, (Hold Option for the Library to show up as its hidden).
Then open Application Support, and you should see CloudDocs there. Move this to the trash or another location as a backup, restart.
If, after the restart, after a few minutes, the data doesn’t show:
Open Finder > Go > Utilities > Activity Monitor:
Search “bird” double click on the process and select “Quit”.
If the data still doesn’t show up:
Click the Apple logo > Force Quit > Finder > Relaunch.
Hope that does it! This maybe a different issue, so further testing and isolating maybe a good idea. But if you get in a rut, give it a shot!