Provided that you have followed the steps in Set up Find My on your iPhone, iPad, iPod touch, or Mac and signed into the same iCloud account on both devices your Mac should appear in Find My on your iPhone - but not in the People tab.
You Mac will - or should - appear in the next tab along called Devices. Is this where you have looked? Is your Mac absent in Devices?
Your iPhone will report its own location in the Me tab on the right.
Over on your Mac, your iPhone will appear in the People tab (as "Me") and the Mac will report its own location in Devices.