Reference:
https://docs.microsoft.com/en-us/azure/active-directory/roles/permissions-reference

Reference:
https://docs.microsoft.com/en-us/azure/active-directory/governance/entitlement-management-overview Overview Contoso, Ltd is a consulting company that has a main office in Montreal offices in London and Seattle.
Contoso has a partnership with a company named Fabrikam, Inc Fabcricam has an Azure Active Diretory (Azure AD) tenant named fabrikam.com.
Existing Environment
The on-premises network of Contoso contains an Active Directory domain named contos.com. The domain contains an organizational unit (OU) named Contoso_Resources. The Contoso_Resoureces OU contains all users and computers.
The Contoso.com Active Directory domain contains the users shown in the following table.

Microsoft 365/Azure Environment
Contoso has an Azure AD tenant named Contoso.com that has the following associated licenses:
Microsoft Office 365 Enterprise E5
Enterprise Mobility + Security
Windows 10 Enterprise E5
Project Plan 3
Azure AD Connect is configured between azure AD and Active Directory Domain Serverless (AD DS). Only the Contoso Resources OU is synced.
Helpdesk administrators routinely use the Microsoft 365 admin center to manage user settings.
User administrators currently use the Microsoft 365 admin center to manually assign licenses, All user have all licenses assigned besides following exception:
The users in the London office have the Microsoft 365 admin center to manually assign licenses. All user have licenses assigned besides the following exceptions:
The users in the London office have the Microsoft 365 Phone System License unassigned.
The users in the Seattle office have the Yammer Enterprise License unassigned.
Security defaults are disabled for Contoso.com.
Contoso uses Azure AD Privileged identity Management (PIM) to project administrator roles.

MFA and SSPR are both required. However, MFA is required first.
Reference:
https://docs.microsoft.com/en-us/azure/active-directory/identity-protection/howto-identity-protection-remediate-unblock
https://docs.microsoft.com/en-us/azure/active-directory/authentication/howto-sspr-deployment

Reference:
https://docs.microsoft.com/en-us/azure/active-directory/governance/access-reviews-overview

Reference:
https://docs.microsoft.com/en-us/azure/active-directory/external-identities/b2b-quickstart-add-guest-usersportal