Built into iOS, iPadOS, macOS, and watchOS, Handoff lets you switch devices while doing the same thing. For example, you can write a document on your iPhone and finish it on your iPad without any additional steps. Likewise, you can start a FaceTime call on your iPhone and switch to your Mac. Here's how to use Handoff on your iPhone.
How to Use Handoff on iPhone
We need to be signed in to the same Apple account on the devices and have Wi-Fi and Bluetooth turned on. The devices need to be in contact with each other to track location using Bluetooth. The feature currently only applies to Safari, Messages, Notes, Mail, Keynote, Pages, Numbers, Calendar, Contacts, Reminders, Maps, News, and FaceTime and requires all your Apple devices.
Step 1:
First, you need to enable Handoff on your iPhone . Go to Settings > General > AirPlay & Continuity, then enable Handoff .
On macOS, go to System Settings > General > AirDrop & Handoff, then turn on Allow Handoff between this Mac and your iCloud devices.
Step 2:
Open a Handoff-supported app on one device. On the other device, you'll see a notification to continue using the app as shown below. On a Mac, click the app icon in the Dock that has a small iPhone, iPad, or Mac icon, indicating the device you'll be working on.

If you receive a notification on your iPhone, we swipe up from the bottom edge of the iPhone screen and you will see a horizontal bar with the name of the application and the device at the bottom to continue working on your iPhone.

If it is an iPad, you will see a device transfer icon for you to click to continue working.

After clicking on that notification, you can continue to complete your work on another device.