HBO Max is available on PlayStation 4 and other home devices through an update to the HBO Now app. However, currently, the HBO Max app does not allow users who have free access with their cable plan to connect with their TV provider's specs. Either way, users can log into the HBO Max service using the TV login page on the HBO Max official website.
To do this, you will need to go to the official HBO Max website on the desktop browser. In particular, PS4 users will initially need to go to Hbomax/tvsignin. This provides the TV provider login page for HBO Max Hbomax.com/tvsignin.