If you wish to Add Another Separate domain into cPanel, there is an option called Addon Domains. Login to your cPanel > “Addon Domains”.
After that Fill in your domain name in the domain name section without www.
Don’t fill subdomain and Document Root. Because it will be auto-filled itself when clicking on somewhere else.
After that press the Add Domain button.
Document Root is the Folder of you must upload your website. It should be in cPanel > File manager > “example.com”. Upload your all website files to the inside of example.com folder.
After that, Update Nameservers on Domain Name.
This Addon Domain option was removed from cPanel version 106.0.1. Please follow this article to add another domain name to a cPanel.