I couldn't find 'iCloud Archive' folder in the Finder. I have been searching it everywhere in the desktop to the different folders, but I couldn't find it. Where do I access it and its contents?
If you signed out of iCloud and kept a local copy, you should have an Archive folder created in your Home folder:
If you turn off iCloud Drive or sign out of iCloud, you have the option to keep a local copy of your files that are in iCloud Drive. Whether you decide to keep a local copy or not, a new Desktop and Documents folder is created in your home folder. If you choose to keep a local copy, your files in iCloud Drive are copied to a folder called iCloud Drive (Archive) in your home folder. Then you have the option to move any files that were in your iCloud Desktop and Documents, back to your new local Desktop and Documents.
There is a possibility that:
You didn't keep a local copy
You moved/deleted the folder
You already emptied the contents of the folder