cPanel/WHM is listening to the ports 2086 and 2087, later when accessed via HTTPS.
You can access the web interface of WHM in your browser by going to http://IPADDRESS:2086 or https://IPADDRESS:2087 for encrypted connection.
This will take you to the WHM login window and since WHM requires ‘Root’ access, you need to login as the Root user and password.
The first page you see after login would be the initialization setup page. This page just shows the license agreement, you can accept it.
In this page you need to specify the following things:
Server Contact Email Address // This is the Email address in which server sends notification Emails.
This Server’s Hostname // Hostname of the server
Primary Resolver // Primary Name Server which this cPanel server contacts to for Domain Name Resolution.
Secondary Resolver // Secondary Name Server which this cPanel server contacts to for Domain Name Resolution, this is set incase the Primary Name Server is not responding or resolving.