You definitely don’t need to worry about a web site if you want to just use the domain for email.
Feel free to hit me up if you have any questions about it. Some providers make it pretty easy I think to setup and manage all of that together, while others require some manual work on your part.
On my home network, devices are backed up using Time Machine over the network. I also use Backblaze to make a second backup of data to their cloud service, using my own private key. Lastly, I throw some backups on a USB drive that I keep in a fire safe.