Azure Notification Hub

Hi.

I have been trying to solve somethig but I have not had good luck.
We are developing a Mobile Application with Xamarin.

Our App have the next requeriments:

1. User Download and install the App in his/her Smartphone
2. When the installation finish, the device got the token from Firebase Cloud Messaging / Apple Push Notification Service.
3. The App sends the device-token to the Back End site. (using REST, Http or similar.)
4. The App register the device-token in Azure, in order to receives notifications from Back End in the future.
5. The Back End sends a Notification Push Request to Azure, including the device-token.
6. Azure use Firebase Cloud Messaging to send a notification push to an specific token device.

I have not clear If I can do this with Azure. I think I can do this using Firebase Cloud Messaging, but I would like to use Azure just in case I would be possible.

I found this link:

https://video2.skills-academy.com/en-us/azure/notification-hubs/notification-hubs-push-notification-registration-management
With this part: "Example code to register with a notification hub from a device using an installation"

I put that code in my Xmarin.Android.Project but I am facing some problems with the Nuget I think I could use
Package Microsoft.WindowsAzure.ConfigurationManager 3.2.3. is not compatible with monoandroid90 (monoAndroid, Version=v9.0).
Package Microsoft.WindowsAzure.ConfigurationManager 3.2.3 supports: net40 (.NetFramework, Version=v4.0)

Is seems It is not possible install that Nuget in Xamarin.Android.Project.

When I try to install Micrisoft.WindowsAzure.ConfigurationManager I receive the message the IDE can not install the nuget in Android Project.

11989-azurehubmessageerror1.png
That is why I need to register the device token in Azure.
I need to execute that code after the App is Installed in the Device.
Is that possible?

I am trying to do this in order to cover the App Requeriments. In this App, it is necesario the Back End and each Device share some information directly. It is soppose the process must begin with the Notification Push sent it from the Back End.

We want to buy some Azure Notification Hub Service, But I need to be sure the Back End can send a custom push notification to one device. I would like to do that using Azure because the have a Hub Notification, else, I would have to configure Firebase directly in the App but I do not want to do that.