When creating a new event in Calendar, click location and add FaceTime. You now have scheduled a FaceTime call!
Schedule Facetime in Calendar
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How to Share a FaceTime link
You can also share a FaceTime link by clicking "Create Link" in FaceTime.
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6 FaceTime Features for Video Calls and Screen Sharing
How to schedule FaceTime calls, blur background, share screen, watch videos together, and use voice isolation