Is this the product you are talking about? If so, check out the user manuals near the bottom of the page: https://www.wdc.com/products/personal-cloud-storage/my-cloud.html
If you want your MacBook to remotely backup to the cloud drive, you'll need to tell Time Machine where to back up to. Once you've set up your cloud drive, open System Preferences, then choose Time Machine. Click on the lock, then enter your administer username and password. Check the box next to "Show Time Machine in menu bar" (for convenience), then click on Select Backup Disk. Your cloud drive should appear in the list. Select it, then log in using the account you created for the drive. Time Machine should soon start backing up to the disk.
Hope this helps!