add non "HomeKit-compatible" camera by IP address

Trying to add an Eaton CAM-EXT-00 security camera to Home even though it's not "HomeKit-comaptible".

I've read instructions for iPhone:

Set up security cameras in Home on iPhone – Apple Support (UK)

and instructions for Home:

View and record video from security cameras in Home on Mac – Apple Support (UK)

all of which are geared for "HomeKit-comaptible" devices only.

Surely there's a way to simply take the stream from the camera's IP, as do most other systems and apps?