The first step in reviewing the Azure subscription for NIST 800-53 compliance is to add the NIST 800-53 regulatory compliance standard in Defender for Cloud. This will allow you to see if your subscription meets the requirements for the NIST 800-53 standard. After adding the standard, you can review the compliance status and take appropriate actions to address any issues found.

Microsoft Defender for Cloud continually compares the configuration of your resources with requirements in industry standards, regulations, and benchmarks. The regulatory compliance dashboard provides insights into your compliance posture based on how you're meeting specific compliance requirements.