Your company operates with a Microsoft 365 ES subscription, an Azure subscription, on-premises applications, and Active Directory Domain Services (AD DS). To enhance the security of your identity management, you need to devise a strategy that fulfills the following criteria:

1. Allow customers to authenticate to an Azure App Service website using their Facebook credentials.
2. Provide partner companies access to specific Microsoft SharePoint Online sites relevant to their assigned projects.

The proposed solution should aim to minimize the deployment of additional infrastructure components. What should your recommendation include?