You log in with two-factor authentication in the same way as for mit.au.dk, office.com, my profile (medarbejdere.au.dk), and many other systems. If you are already logged into another AU service that uses the same login method, you do not need to enter your login and password again; you will instead be automatically logged into TYPO3. You can read more about two-factor authentication here.
After the two-factor authentication, you will see an overview of the TYPO3 pages you are an editor for. Click on 'Go to website.' If you are missing access to a page, please contact your local TYPO3-support.