Hi,mariiaksonova,maybe i can help you. The document you are referring to talks about Time Machine. All you need to use it is a properly formatted hard drive or external SSD of some kind with the same rough capacity( size) as the ssd/ hard drive in your iMac Pro, and plugged into it( usb or Ethernet?) I think Time Machine is under system preferences/ or under Applications. You just turn it on, and point it to the drive you want to use as a Time Machine backup. Then tell it to do a backup and it does it. You can also schedule weekly and monthly backups. You can also restore from a Time Machine backup
hope that helps
john b