Does my MacBook also share my iCloud account?

See the article iCloud Drive FAQ - Apple Support

• On your Mac, you can go to iCloud Drive in Finder.

When you add your Desktop and Documents to iCloud Drive, all of your files move to iCloud. On your Mac, you can find the files on your Desktop and in your Documents folder in Finder under iCloud.

You can if you go to System Preferences/Apple ID/iCloud, sign in with the same Apple ID that was used to sync the files to iCloud, and then turn the desired syncing on. The iCloud sync is very, very slow. The photos sync is extremely slow. It could take several days or more for the photos to sync.