How to track phones using serial number

Find My is the only way to track your phone.....assuming some other things like.....

You enabled Find My on the phone before it was lost

The battery is still good

The phone has an Internet connection where it is currently located

Find your lost iPhone or iPad with Find My - Apple Support

You can’t. If you didn’t have Find My active on the stolen phone you won’t be able to track it

That is not possible.