You can restore content from an iCloud backup when, for instance, you update the tablet software. To restore the content, you need to back up the tablet memory to iCloud.
You can restore content from an iCloud backup when your tablet is activated for the first time and after a factory reset. When this screen is displayed, your tablet is ready to restore content from an iCloud backup.
Press Restore from iCloud Backup.
Press the field next to "Apple ID" and key in the username for your Apple ID.
Press the field next to "Password" and key in the password for your Apple ID.
Press the required backup and your tablet restores the content of the selected backup. Subsequently, follow the instructions on the screen to set up your tablet and prepare it for use.