Using MacBook Pro 2019 as a second monitor (or vice versa)

Erklee102381 wrote:

I have searched high and low can can't seem to find what I am looking for, it may not even be possible. I have a 16" 2019 MacBook Pro and a iMac (Retina 5K, 27-inch, 2019). I am wanting to use the MacBook Pro as a a second monitor for when I am working on certain things but I can't quite figure out how. I have connected the two using a thunderbolt cord and tried hitting command+F2 on the device I want to use as a display as various other websites has suggested but I am not having any look. So is this even possible?

This is not possible.

Use your iMac as a display with target display mode - Apple Support

you can read more: https://discussions.apple.com/thread/251361476

Use your iPad as a second display for your Mac with Sidecar ...

Use external monitors with your Mac - Apple Support

Nope. Not going to happen. Target Display mode was deprecated long ago and is not supported on anything running anything later than High Sierra.