Choose an external camera on Mac
Many Mac computers have a built-in camera located near the top edge of the screen, but you can also use an external camera with your Mac—including the the camera on recent iPhone models.
Connect the camera to your Mac using the appropriate cable or wirelessly (depending on the camera).
Open an app that captures video, then do one of the following:
FaceTime: Click Video in the menu bar, then choose a camera.
Photo Booth: Click Camera in the menu bar, then choose a camera.
QuickTime Player: Choose File > New Movie Recording, hold the pointer over the window, click the down arrow
, then choose a camera.Head pointer accessibility feature: Choose Apple menu
in the sidebar. (You may need to scroll down.) Click Pointer Control, click the info button 
next to “Head pointer,” click Camera Options, then choose a camera.Third-party apps: You may be able to use your external camera with third-party apps you downloaded from the App Store. To find out how, read the developer’s instructions or explore the app’s menus and settings.
