Set up NPS (or any other RADIUS server), point that to your Azure AD.
Afterwards, set up your MX to do RADIUS to your RADIUS server: https://documentation.meraki.com/MR/Encryption_and_Authentication/Configuring_RADIUS_Authentication_...
NPS is Microsofts RADIUS server implementation: https://docs.microsoft.com/en-us/windows-server/networking/technologies/nps/nps-top
It features an Azure AD connector so you‘re able to leverage your users in the cloud:
You can't use NPS with Azure AD. You can only use it if you are AD syncing with Azure, and then it runs against AD. The link with Azure AD is only an extra step for MFA.