Apple CarPlay uses the contacts on your iPhone to help you make calls when you’re on the move. Tap the Phone icon then tell Siri to call your contact. and when finished, simply tap end on the touchscreen or press the end call button on the steering wheel.
You can also access your voice messages, by asking Siri ‘What voicemails have I got?’ which will then play your messages and if you want to return your last call, simple Tell Siri ‘Return my last call’.
To receive a call is just as easy, when your phone rings press the call button on your steering wheel.