Hi @Punditji
Before external users can connect to your deployment, you need to enroll your subscription in per-user access pricing. Per-user access pricing lets users outside of your organization access apps and desktops in your subscription. Your enrolled subscription will be charged each month based on the number of distinct users that connect to Azure Virtual Desktop resources.
https://learn.microsoft.com/en-us/azure/virtual-desktop/remote-app-streaming/per-user-access-pricing
For streaming RemoteApps and desktops to external users. For example, a software vendor called Contoso might use Azure Virtual Desktop to serve remote streams of Contoso’s productivity app to Contoso’s customers (users who aren't Contoso employees). In this case, Contoso must enroll in Azure Virtual Desktop’s per-user access pricing. This license type lets Contoso pay for Azure Virtual Desktop access rights on behalf of those users through an Azure meter based on the number of users who access Azure Virtual Desktop each month. The users in the deployment don't need a separate license like Microsoft 365 to access Azure Virtual Desktop.
https://learn.microsoft.com/en-us/azure/virtual-desktop/remote-app-streaming/licensing#licensing-azure-virtual-desktop-for-external-users
For more details this question is already explained in Q & A forum.
https://learn.microsoft.com/en-us/answers/questions/496721/is-azure-virtual-desktop-working-with-azuread-exte.html
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