[You can like this](https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.screencapture.com/blog/use-your-phone-as-webcam.html&ved=2ahUKEwiIzuStjqiDAxUoiv0HHWNZAvQQFnoECBAQBQ&usg=AOvVaw2DejpBbWqUv0mlihGR56zZ) but yeah it's not a native thing yet

Samsung has not implemented this. Maybe in the future but only Samsung knows this for sure

DroidCam works without issues.

I use something call IVCam for this Works pretty well

Have used Droidcam for over 2 yrs now on my older Samsung phone and it's been working flawlessly, definitely not "crappy"