A function to a store in Shopify

I'm working on a website development project and need support to help me understand better.

It is a website that sells geolocated items. The idea is for the client to enter some coordinates and I receive an order with the coordinates that the client has entered. The products are already added and the coordinates can be chosen with the mapbox. What is needed is to implement a function so that the coordinates marked by the customer appear in the cart and in the Orders section, so that I can know which are the coordinates that the customer enters.

Sample Solution