Officially one cannot a computer to a single bay My Cloud located at a remote location using WD software. At best one could “sync” folders from a their computer to a remote My Cloud. Or one could use FTP. Smartware, the included backup software with the My Cloud, is local network only for backup to the My Cloud. One can read the Smartware User Manual (http://www.wdc.com/wdproducts/library/UM/ENG/4779-705057.pdf) to see how Smartware works.
There used to be a way using remote mapping through the WD2Go.com web portal but that remote mapping option was removed when WD released the OS 3 firmware and changed WD2Go.com to MyCloud.com.
Unofficially there are several ways, some may involve using SSH to setup a remote backup method. Another is to use a VPN tunnel. One way is to install the WebDAVMod and map the remote My Cloud. From there one can use backup software to backup to the mapped Share on the remote My Cloud.
https://community.wd.com/t/app-clouddavmod-v1-0-for-firmware-v4-04-2016/161543
Other methods are discussed in other threads where a similar question was asked. Here are just a few of those posts/threads:
https://community.wd.com/t/remote-access-and-backup/161471/2
