Feel free to add your voice to several threads asking for backup to remote offsite cloud storage services in the Cloud Ideas subforum. Do a search of that forum and you’ll find numerous threads asking for such a feature.
https://community.wd.com/c/personal-cloud-storage/cloud-ideas
Generally there are several methods one can use to upload their single bay My Cloud content to Dropbox and other similar sites. One is to map the My Cloud to your local computer then use the Dropbox or similar service software program to upload the content you select. Another other option, if the remote service supports it, is to use Rsync or similar Linux command from the My Cloud SSH command line to upload content to the online storage location.
If you do a search of this subforum you’ll see Dropbox and similar support is often requested. Here are just a few of those previous threads with some suggested options for accomplishing such a request.
https://community.wd.com/t/backup-of-my-cloud-to-amazon-cloud-and-or-idrive-backup-service/156620
