Shopify Apps Validation Team is requesting us to add the "Feature list details on the Billing Modal prompt", see their red square in the screenshot here bellow, however there is no such Admin Rest API option as we can see here:
This is a shopify page which is not part of the app. How do we set the feature list to be displayed there?
After looking into your question and the resource shared, I would suggest working though each step of this implementation tutorial for the REST Billing API as a starting point. If you have any questions about the review process or any feedback that was provided, feel free to contact our Partner Support team directly from the Support menu in your Partner Dashboard - Cheers!