Download Microsoft Security, Compliance, and Identity Fundamentals.DrunkMonk.SC-900.2021-07-01.1e.46q.vcex

Reference:
https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/get-started/

Reference:
https://docs.microsoft.com/en-us/azure/security/fundamentals/customer-lockbox-overview

Federation is a collection of domains that have established trust.  
Reference:
https://docs.microsoft.com/en-us/azure/active-directory/hybrid/whatis-fed

Box 1: Yes
System updates reduces security vulnerabilities, and provide a more stable environment for end users. Not applying updates leaves unpatched vulnerabilities and results in environments that are susceptible to attacks. 
Box 2: Yes
Box 3: Yes
If you only use a password to authenticate a user, it leaves an attack vector open. With MFA enabled, your accounts are more secure. 
Reference:
https://docs.microsoft.com/en-us/azure/security-center/secure-score-security-controls

Reference:
https://docs.microsoft.com/en-us/microsoft-365/compliance/compliance-manager?view=o365-worldwide
https://docs.microsoft.com/en-us/microsoft-365/compliance/compliance-score-calculation?view=o365-worldwide

To on-board Azure Sentinel, you first need to connect to your security sources. Azure Sentinel comes with a number of connectors for Microsoft solutions, including Microsoft 365 Defender solutions, and Microsoft 365sources, including Office 365, Azure AD, Microsoft Defender for Identity, and Microsoft Cloud App Security, etc. 
Reference:
https://docs.microsoft.com/en-us/azure/sentinel/overview

The Microsoft Service Trust Portal contains details about Microsoft's implementation of controls and processes that protect our cloud services and the customer data therein. 
Reference:
https://docs.microsoft.com/en-us/microsoft-365/compliance/get-started-with-service-trust-portal?view=o365-worldwide