There are numerous ways to have the live preview of an IP camera like the CM7x series:


- From the web Gui camera itself:

* The live preview of the CM7x web gui only works if the main stream is set to 'H264'

* It can be set to Full screen if desired

* See How to open the camera's web GUI?



- From PC softwares, like those free ones below:


Onvif Device Manager

* Like on the camera web GUI, it is also possible to control the camera (from the 'PTZ Control' tab)

* See Using ONVIF Device Manager with Avonic IP cameras


Potplayer

* It can be set to Full screen if desired

* See How can I use Potplayer to view the camera RTSP stream?



VLC

* It can be set to Full screen if desired

* See How can I use VLC to view the cameras' RTSP stream?



OBS Studio

* See Stream an Avonic Camera via RTSP to OBS and control presets via third party Plug-IN

* See Stream an Avonic NDI camera to OBS



You can also use the IP Camera Viewer software as described in that article