You can pick someone in Teams to be your delegate or receive and make calls on your behalf. When you add a delegate, you’re essentially sharing your phone line with them, so they can see and share all of your calls.
Select Settings and more 
next to your profile picture at the top of Teams and choose General.
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Your delegate will receive a notification letting them know about their new status.
Your new delegate will now appear in your delegates list.
Go to Settings > Calls. Under Forward my calls, you'll see My delegates as the default Forward to option.
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