Using a Campark ACT74 action cam as a webcam in macOS 10.12

I recently got a Campark ACT74 action cam, with the intention of using it as a camera with which to live-stream stuff to Twitch and the like. Upon plugging it in to my Macbook Pro (2015, 10.12) --- nothing happens. It doesn't appear in OBS, PhotoBooth or QuickTime, despite selecting the "PC Camera" option when prompted by the camera upon plugging it in. I tried getting it to work with the open-source "macam" software, but that didn't recognize it either.

How can I make this camera work with macOS?

According to the User Manual available here this actioncam cannot be used as a webcam. The prompt you get upon connecting the device via USB lets you probably choose between Mass Storage (UMS) Protocol and Camera (usually abbreviated PTP - Picture Transfer Protocol).

Both protocols let you transfer pictures from the actioncam to your Mac/PC but neither of those allows the camera to be used as a webcam. That's the reason why it will not show up in any of the mentioned applications in your question.

However, if you have a HDMI capture card or a device to capture HDMI input, you could theoretically capture the output of the actioncam using the HDMI output of the camera on the side. If you don't have such a card you are probably better off just buying a webcam supported by macOS since those HDMI capture cards are more expensive than a webcam.

The above answer is not completely accurate. This model will work as a web camera, but I have only been successful in getting it to work on my work PC. When the camera is plugged into a USB port, a menu will pop up asking you to select between three modes: USB Mode, PC Camera, or Charge Mode. The manual does not address these modes for some unknown reason.

Selecting PC Camera will put the Campark ACT74 action cam into webcam mode. This works fine on my Dell Latitude 3390, once Windows finished setting up the device (which it interestingly calls "android"). The same does NOT work on either my Mac Pro or my MacBook pro. The camera will go into webcam mode just fine, but the computer will not recognize it and it cannot be used.

If anyone has a more concrete answer as to why this doesn't work, I would greatly appreciate it.