My I phone 12 pro is global but my i phone buying receipt is missing

You are responsible for saving your receipts for anything you buy. If you bought the phone from Apple.com you can log in to the site and see a history of your purchases, but if you bought from a store all you will have is the store receipt.

I’m puzzled what you mean that your iPhone is “global”. There is no such thing as a global iPhone; different countries and different regions each have their own iPhone model that meets the government requirements for that country. And an iPhone’s warranty is only valid in the country where it was originally intended to be sold.