The Office 365 portal for organizations with Office 365 Small Business, Office 365 Small Business Premium, and the Windows Intune portal does not have the user interface to enable Multi-Factor Authentication for their users.
To enable Multi-Factor Authentication for users in these organizations, here is the workaround …
|Office 365 Small Business
Office 365 Small Business Premium
1. Sign in to the cloud service portal as an admin.
3. On the multi-factor authentication page, enable Multi-Factor Authentication for admins and users.