After learning what WHM was, I next needed to find out how to get to it. (Because it's obviously not accessible from cpanel X.) I found out how to access the log-in using these instructions for initial set-up.
To access the WHM interface:
1. Type
https://IP:2087 in your preferred web browser.
* IP is meant to stand for the IP address of your web server.
2. Use root as the login name in the Name field.
3. Enter the password into the Password field.
4. Click Log In.
The problem is, it doesn't work. I found out that my package doesn't support WHM. At least I'm not as inept as I thought. Thanks for your help Spiral.