Apple has announced that the move from iCloud Documents & Data to the iCloud Drive service has finished.

In May of 2021 the Cupertino-based company said that to eliminate confusion and streamline iCloud storage it will be discontinuing Documents & Data and relocating it to iCloud Drive. That promise has been completed 12 months later.
Users can now sync their files between several devices and apps automatically under the iCloud Documents & Data. Apple updated its support page and said that iCloud Documents & Data has been discontinued, with iCloud Drive taking its place. Legacy service accounts will be automatically moved to iCloud Drive without users needing further action.
Apple reminds users that they will need to enable their iCloud Drive to see the files. To do this on an iPad or iPhone, users can go to Settings, then iCloud and enable the service to be able to view the files in the Files app. On macOS, it can be done via System Preferences, then iCloud and iCloud Drive.