You can remotely control another person's iPhone, iPad, and Mac using FaceTime. This requires you to use Facetime's screen sharing feature and request control of the other person's device.

To use Switch control on your iPhone, connect your iPhone and iPad to the same Wi-Fi network and log in to the iCloud account on both devices using the same Apple ID.

On the Mac, click the button with a purple screen icon in the top-left corner of the screen sharing window and select the dimmed Allow Control button. How to Remotely Control Another iPhone or Mac ...