Hi @Gokul R Dev ,
Azure Virtual Desktop doesn't currently support external identities, including business-to-business (B2B) or business-to-client (B2C) users. You'll need to create and manage these identities manually and provide the credentials to your users yourself. Users will then use these identities to access resources in Azure Virtual Desktop.
To provide a secure solution to your customers, Microsoft strongly recommends creating an Azure Active Directory (Azure AD) tenant and subscription for each customer with their own dedicated Active Directory. This separation means you'll have to create a separate Azure Virtual Desktop deployment for each organization that's totally isolated from the other deployments and their resources. The virtual machines that each organization uses shouldn't be able to access the resources of other companies to keep information secure. You can set up these separate deployments by using either a combination of Active Directory Domain Services (AD DS) and Azure AD Connect or by using Azure AD Domain Services.
Check this page and information provide should be a good start to understand the model licensing
Hope this helps.
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