( i’ve moved this to projects so you can get answers specific to your own set up. )
To the best of my knowledge, you can’t do this with any of the cameras on the official compatibility list so far. If a camera has an IFTTT channel that exposes the motion sensor, you can do it that way. I think some members may have done some custom code that allows it with other camera models. But others can say more. (I have security cameras but I don’t use them with SmartThings.)
@rboy is an independent developer who offers paid apps and has done a lot of work with blink. I believe his paid device handler will allow you to use the blink as a motion sensor
I know quite a few community members have used Arlo, and hopefully some of them will chime in. The Arlo has an IFTTT channel which lets you use both its motion sensor and its audio sensor (if you have the model with an audio sensor)
@smart has nest cams, but I believe his experience was that they motion event could not be captured for use by smartthings. He can say more.
@pstuart has done a great deal with many different types of cameras, and might also have more to say.
@tyler might know if additional integration with Samsung cameras would offer this ability and if so when it might be planned for the future.
You’ve probably already seen this, but this is the list of the officially compatible cameras
https://support.smartthings.com/hc/en-us/articles/205380804-Video-integration-with-Hub-v2-FAQ