Hi Marouf Ali,
Welcome to Microsoft Q&A Forum, thank you for posting your query here!
When migrating from Microsoft 2016 to Microsoft 365 and Azure Blob Storage, the resources fall under different cloud service models
Microsoft 365: This is a (SaaS) model. It provides users with access to Microsoft Office applications and other productivity services over the internet.
Azure Blob Storage: This is part of the (IaaS) model. It offers scalable object storage for unstructured data, such as documents, images, and videos.
So, in this scenario, you would be using both SaaS (for Microsoft 365) and IaaS (for Azure Blob Storage)
For more detailed information:
https://learn.microsoft.com/en-us/azure/storage/common/storage-migration-overview
https://techcommunity.microsoft.com/blog/azurestorageblog/reflecting-on-the-first-year-and-future-of-the-azure-storage-migration-program/3720451
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