Center Stage is a feature available on the M1 iPad Pros:
11-inch iPad Pro (3rd generation)
12.9 inch iPad Pro (5th generation)
This feature uses the front-facing camera (Ultra Wide lens) to automatically keep the person (or people) on camera in frame. As the person moves around, the camera pans to follow them.
You can take advantage of the feature while using Switcher Studio by enabling Center Stage as follows:
Go to Settings on the iPad Pro
Tap Switcher Studio.
Tap the toggle next to Center Stage to turn it on (when enabled the toggle is green).
After that, when you are using the front-facing camera as a source in Switcher Studio, Center Stage will be active.