Hi Kadek Ardana,Thanks for reaching out to Microsoft!
Currently, retrieving the Booking Duration (hours) and Booking Window (days) through the Graph API is not supported.
However, you can fetch this information using Exchange PowerShell with the following command:
Get-CalendarProcessing -Identity "RoomMailbox Address" | fl
Since this feature/functionality is presently not available, you can submit a feature request idea using support link, which will be monitored by Microsoft team and make the enhancements to Microsoft Graph APIs.
Hope this helps.
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