I have a project that I use for testing new things and I'm using the MSDN subscription, however most of it is used by ATP and Security Center.
Is there any way for me to turn this off? My subscription gets disabled every month since it goes over the spending limit.
Defender for Cloud (formerly named Azure Security Center) can be enabled/disabled on the subscription level, which will take effect on all SQL databases or it can be enabled per SQL database. To enable / disable it, go to the relevant SQL database, navigate to Microsoft Defender for Cloud on the left pane and check the 'Enablement Status' then click 'Configure'
For more info refer to https://learn.microsoft.com/en-us/azure/azure-sql/database/threat-detection-configure?view=azuresql