Yes, things like Preview, Books, Numbers files, Pages files, Mail, etc… but in terms of actual Folders the iCloud Drive will only contain the Desktop and the Documents folders (and everything within those two folders).
It is all very well documented. I suggest the OP takes some time to read the links I posted earlier.
It's not limited to just the Desktop and Documents folder though (or the others you mentioned). iCloud Drive is Apple's equivalent of Dropbox, OneDrive, or Google Drive; and behaves very similar to those. You can put
anything you want in your iCloud Drive through Finder, which is what the OP did. I have 'Desktop & Documents Folders' turned off, so those folders don't show even up for me. I have my own folders that I created and work with them through iCloud Drive in Finder. All my files (pictures, videos, PDFs, zip files, Word, Excel, DMGs, EXEs, etc.) show up on my iPad, iPhone, iCloud.com, and even on my Windows PC with 'iCloud for Windows' installed.
With that said, iCloud Drive is known to not be very reliable sometimes compared to other services.
@SkiHound2, another thing you could check is to see if your folder/files have actually uploaded to the cloud by viewing your iCloud Drive at iCloud.com. That would help us determine if you're having issues uploading from the iMac, or downloading on the MacBook. If they're not visible at iCloud.com, you could try uploading them through there and then see if they show up on the MacBook. Also out of curiosity, does your iCloud Drive work in reverse? If you put something in there from the MacBook, does it show up on the iMac?