Return all files from iCloud

iCloud storage has all of my documents, music, pictures, etc. My intention was to select a folder from my iMac and keep it in iCloud. NOT every file on my hard drive. My network is limited to the devices I have at home. I can easily share documents between the devices. They do not need to be on iCloud for my purposes. PLEASE RETURN MY FILES TO MY IMAC HARD DRIVE. Thank you.