If you have an iPhone and a Mac or iPad, you can link your phone number to your iCloud account to send and receive calls and messages from the same number on both devices.
Add a New or Existing Number on iOS
You’ll need to make sure your devices are signed in to the same iCloud account for everything to sync correctly.
The process is the same for all iOS devices, but you’ll need to enable your existing number on your iPhone first. On your phone, open the Settings app.
Tap on the category marked “Messages.”
Make sure you’re signed in and have iMessage turned on. Scroll down and tap “Send & Receive.”
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Source: How-To Geek
