Suppose I lost my phone and I could use find my phone to find it. The problem is I don’t have my phone in order to find my phone with. I don’t have a computer I don’t have a laptop All I have is a phone. How on earth would I use find my phone to find my phone?
Ask someone else with a phone.
Use a library/work computer.
I’m pretty sure a phone store of your carrier could also help you. I’m 99% positive I’ve seen them advertising such support at my local TMO.
I bet your provider probably has some way to help you find your device.
They can triangulate you to within a building, maybe even a specific room, but they won’t unless you’re with the authorities and have a warrant. There’s a small exception to that, some American carriers are known to sell live location data to bounty hunters, but you’d have to pay more than the price of a new phone to get access to that.
Still won’t help you find your phone if it’s slid under a cupboard, though. But if you can reach your carrier, you can call your phone.