Well, that is a bit atypical as headless seems to be the trend for CMS’s, but that addon can make Cockpit work like a traditional CMS, by serving directly pages. More details on https://github.com/pauloamgomes/CockpitCMS-HBmode
I would recommend to use cockpit in a subfolder and add a index.php file which loads cockpitfolder/bootstrap.php and then handles the routes.
Yeah, that can be a better approach, the addon/idea was mostly an experiment…