I have a server with WHM installed for cPanel accounts. This comes with its own Apache configuration.
If I hit either the domain for this server (without a userdir temp url), or the IP, I get the default Apache landing page (cgi-sys/defaultwebpage.cgi).
I'd like to instead specify a folder on the server that would serve as this landing page/website. How do you modify WHM or the Apache settings to accomplish this (without screwing up WHM/cPanel in the process)?
Since you have mentioned WHM, an easier way to do would be to use the web editor feature provided by WHM itself to custom make the default page instead of the one shipped by cPanel.
Web template editor in WHM can be found in account section.
If needed, this tutorial might help you : https://www.basezap.com/change-cpanel-default-pages/