Starting a call from MacBook - Your iPhone needs to use the same iCloud and Facetime
To see devices attached to an account:

Sign into the Apple iCloud via a browser as the account you want to check
Drop down the arrow next to your name (top right)
Choose 'Settings'

The screen will then show you devices that are attached to that account.
The device MUST be running iOS 8, macOS Yosemite, or watchOS 1 or above (not an issue in your case).