To allow the Windows Admin Center gateway to communicate with Azure to leverage Azure Active Directory authentication for gateway access, or to create Azure resources on your behalf (for example, to protect VMs managed in Windows Admin Center using Azure Site Recovery), you will need to first register your Windows Admin Center gateway with Azure. You only need to do this once for your Windows Admin Center gateway – the setting is preserved when you update your gateway to a newer version.
In the following Step-by-Step Guide you will connect Windows Admin Center to your Microsoft Azure Subscription.
From here you have to copy the device Code and hit the Link device login ( https://aka.ms/devicelogin )
This will make the connection between Windows Admin Center and your Azure Subscription.
Paste the Code into here and Click on Continue.
Sign in your Azure Subscription.
From here you are connected to your Azure Subscription.
Select the right Azure Tenant and Click on Register.
Go to the Azure AD App Registration link.
Click on Settings
Click on Required Permissions and then on Grant permissions
Click on Yes.
Windows Admin Center has now Permission.
Microsoft Windows Admin Center (WAC) Gateway is now registered to your Azure Subscription and you can use Azure AD Multi-Factor Authentication and Azure Site Recovery to protect your Virtual Machines with WAC.
Networking Settings of the Azure VM.
Open for http WAC port 5985 and for https 5986.
Now you have done this for Azure Networking in the portal, you have to do the same in the Firewall settings of the Virtual Machine Inside.
Allow Port 5985 and 5986.
More information about Azure Integration in Windows Admin Center here
Here you see my Azure VM in Windows Admin Center On-Premises.