With Handoff, you can continue on one device where you left off on another. Start a FaceTime call on your iPhone, then transfer the call to your iMac when you get back to your desk. Or work on a presentation on your iMac, then continue on your iPad. View a message on your Apple Watch, and respond to it on your iMac. Handoff works with FaceTime, Safari, Mail, Calendar, Contacts, Maps, Messages, Notes, Reminders, Keynote, Numbers, and Pages.
Note: To use Handoff, you need an iPhone or iPod touch with iOS 8 or later, or an iPad with iPadOS installed. Make sure your iMac, iOS device, or iPadOS device have Wi-Fi and Bluetooth turned on and are signed in with the same in the upper left of your iPhone or iPad, tap Switch, then tap Switch again.
Turn on Handoff on your iMac. Open Pick up where you left off with Handoff in the macOS User Guide.