External Drive Automatic Backup

The main reason I am communicating with WD is to get your recommendation(s) as to the currently available new WD external disk drive that I can buy, to back up an older WD MyCloud drive that I have. The following are stipulations that impact the capabilities of the new drive I purchase:

1 – The older drive I want to back up is a 3TB WDBCTL0030HWT that is working well. I use this drive to store and access my working files. I access these files by WIFI from 4 computers around my house.

2 – I want the back-ups to automatically occur every night.

3 - I plan for these Ethernet back-ups to be through my 3 module eero WIFI system, from one module in my office to a second module at the other end of the house, with Ethernet connection from this second module to the drive you recommend.

4 - My intent for now is that neither of these external drives be accessible through the internet.

5 - I want the file structures for both of these external drives to to show up under “Network” in Windows 10 File Explorer and for the individual files to be accessible using File Explorer…on all 4 computers.

Please recommend one or more available WD drives (with advantages of each if more than one). Please reply with questions if you have any. Simplicity of setup is desired but not mandatory.

Thank You