How In App Purchase works? And how implement using React Native?

The above image is a research that I due to understand how is the flow necessary to use In App Purchase.
You need submit a version to the store for create products
The first thing is, using the store (Apple or Google) you will create new products that will have a price, but, for made this, you need submit a version alpha, beta, or production, and then so you can create new products.
Identify products available
Using the plugin In App Purchase you have some functions necessary to connect, identify the products and select, and then, show the prompt for the user pay.
Test
Both stores have a way to test payments:
- Google: https://developer.android.com/google/play/billing/test
- Apple: https://developer.apple.com/apple-pay/sandbox-testing/
A Complete Guide to In-App Purchases for iOS Development
This massive guide walks you through the steps to implement in-app purchase (IAP) on iOS apps, written in Swift. Learn how to make extra profits from your apps.
