To set up multi-factor authentication (MFA) for Office 365 users you will need an Admin user account to enable MFA support.
For more information please follow the links below to the external Microsoft docs webpage:
How to enable the MFA on the Office 365 Admin panel.
How to create an MFA password on Office 365 personal account.
Create an app password for Office 365
After you enable multi-factor authentication (MFA) in the Office 365 Admin panel you will have to re-log with your newly created password into the Room Booking System Web Portal account.
Log in to your Room Booking System Web Portal and navigate to "Settings > Calendar", then click on the "Change calendar type" button. Now log in with your current user and your newly created password.