To Publish the App in store. First you need to create the app service in Azure portal.
After successfully creating the app service you will get the Url-
http://<app-name>.azurewebsites.net
.
you need to replace the above URL with the ngrok & valid domain section.
To Create the app service please follow the below documentation-
https://learn.microsoft.com/en-us/azure/app-service/quickstart-dotnetcore?pivots=development-environment-azure-portal&tabs=net70