Make a Group FaceTime call on Mac
When you’re on a FaceTime call, you can add more people to the call (up to a maximum of 32 other people) even if you didn’t start the call.
For information about system requirements for using FaceTime, see FaceTime requirements.
In the FaceTime app
on your Mac, click the Sidebar button 
during a call.Click the Add Person button
, then enter the email address or phone number of the person you want to call. If you have a card for the person in Contacts, you can just enter the person’s name.If you’re restricted to calls with only certain people, an hourglass icon
appears next to those people you can’t call.Click Add.
Each participant appears in a tile on the screen. When a participant speaks, or you click a tile, that tile moves to the front and becomes more prominent. Tiles that can’t fit on the screen appear in a row at the bottom. To find a participant you don’t see, scroll through the row.
Tip: To prevent the tile of the person speaking from becoming larger, deselect the option in FaceTime preferences—choose FaceTime > Preferences, click Settings, then deselect Speaking under Automatic Prominence.
To send an audible alert to a caller who hasn’t yet joined the call, click the Sidebar button , then click Ring.