Two control panels, two levels.
WHM (WEB HOST MANAGER)
Your panel. From here you create cPanel accounts, define packages, suspend and unsuspend clients, set up branding, manage DNS zones and view account listings.
Access it at yourdomain.com/whm or on port 2087, with the reseller username and password from your welcome email.
CPANEL
Each account you create has its own cPanel, used by that client to manage their files, email and databases. They see only their own account.
WHAT YOU CAN AND CANNOT DO IN WHM
You can: create, modify, suspend, terminate and list accounts; define packages; set quotas; log in to any of your clients' cPanels; manage DNS zones for your accounts; set up private nameservers; brand the panel.
You cannot: reboot the server, install system software, change PHP versions server-wide, edit server configuration files, or access other resellers' accounts. Those are server-level functions and remain with us.
WHERE TO START
Log in to WHM, create a package first, then create your first account using it. Doing it in that order saves repeating yourself.