Thank you for your question! I understand that you are looking to see which subscription and licenses you will need if your users are all e3 and e5 and you are using Azure for a healthcare entity.
Azure offers free, pay-as-you-go, and member subscriptions. The Pay-As-You-Go subscription allows you to pay for the services and resources that you use on a monthly basis, and the member/Enterprise Agreement subscriptions offer discounts. More details about these offerings can be found here: https://learn.microsoft.com/en-us/azure/cost-management-billing/understand/understand-usage
As for licenses, all Azure products are licensed per user, so your licensing requirements would depend on which services you want to use. The EMS E5 license comes with the Azure AD Premium P2 license, so you should be good to go for most things there.
For more details about your specific needs, I would recommend speaking with a licensing representative by creating a free ticket with billing support. They will be able to help provide guidance for your scenario. https://azure.microsoft.com/en-us/support/options/
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