Hi @Alessandro Tiberti Bertin ,
Welcome to Microsoft Q&A!
SQL Server Developer is a full-featured free edition, licensed for use as a development and test database in a non-production environment. Both Power BI and DAX Studio are free tools.
For Windows Server, which version do you want to choose?
For more License issue, we suggest that you could consult professionals. Please call 1-800-426-9400, Monday to Friday, 6:00 A.M. to 6:00 P.M. (Pacific Time) to directly speak to a Microsoft licensing specialist. For international customers, please use the https://www.microsoft.com/en-us/licensing/worldwide to find contact information. Or you could get help from Volume Licensing Service Center support.
Best regards,
Carrin
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