Phone calls and text messages on your Mac
You can take calls—and make them—right from your iMac. You can also receive and send text messages.
Note: A Wi-Fi connection is required in order to make or receive phone calls on your iMac.
Set up FaceTime for phone calls. On your iPhone, go to Settings > Phone and enable Wi-Fi calling on your iPhone (iOS 9 or later). Then, on your Mac, go to FaceTime > Preferences, choose Settings, then click “Calls from iPhone.” See the Apple Support article Set up your iPhone and FaceTime on Mac for phone calls.
Take or make a call. When someone calls your iPhone, click the notification that appears on your iMac screen. Your iMac becomes a speakerphone if you’re not wearing headphones. To make a call from your Mac, open FaceTime and enter a phone number. Or, in Contacts, click the phone icon 
in the FaceTime row for a contact. You can also click a phone number in a Spotlight search or in an app such as Safari or Calendar (your iPhone or iPad with a cellular connection must be nearby). See Make and receive phone calls in FaceTime on Mac in the FaceTime User Guide.
Tip: To temporarily turn off notifications about phone calls, messages, and more on your Mac, turn on the Do Not Disturb feature. Click the Control Center icon 
in the menu bar, then click Do Not Disturb and choose a time limit.
Send and receive messages. Use iMessage to send unlimited messages to friends who use Mac, iOS devices, iPadOS devices, and Apple Watch. Send and receive SMS or MMS text messages right from your iMac. When friends and family text you, you can respond with whichever device is closest. All messages appear on your iMac, iPhone, iPad, iPod touch, and Apple Watch. See Messages.
Learn more. See Set up iPhone to get SMS texts on Mac in the Messages User Guide.