I have Azure Datawarehouse which has fixed pricing tier DW100. Usage is small and assuming that Serverless can be cheaper.
A) How do get information how much data processing have been occurring in last month to analyze costs? B) How to do migration to Serverless?
Under Configure choose "General Purpose", you will have the choice between:
You can also shift your current databases from Provisioned to Serverless. In the picture you have to do it one by one but probably there must be a way to do that in bulk through Azure PowerShell.