Northern Trail Outfitters (NTO) has a requirement to ensure all user logins include a single...

Create and assign a permission set to all employees that includes "MFA for User Interface Logins."

Create a custom login flow that enforces MFA and assign it to a permission set. Then assign the permission set to all employees.

Enable "MFA for User Interface Logins" for your organization fromSetup -> Identity Verification.

For all employee profiles, set the Session Level Required at Login to High Assurance and add the corporate identity provider to the High Assurance list for the org's Session Security Levels.