Thank you for that info @domjh. That actually helped a lot!
I wasn’t sure which type of record to add or how to add it, so I’ll tell what I did in case it might help someone else down the road.
You go to the DNS tab and click +Add Record.
You want to add an A record. In the “Name” box just type the third-level domain portion. So in the example of “
whatever.example.com” you would just need to type “whatever”. (If you type the whole thing it will simply strip the part it doesn’t need so it doesn’t really make any difference either way).
Under IP address put in the IP address of your actual site/server, as you’ll see is already listed for the records that have been created automatically by Cloudflare.
Click Save and it should work right away.