As of 2022, UofT has an extensive licensing agreement with Microsoft, for a variety of services:
In summer 2022 the University revised the details of the Microsoft Campus Agreement, affecting what variants and versions of Office are provided to whom.
See MS Campus Agreement for details of these updates.
There are also options to purchase individual licenses for Microsoft software through uSource /Licensed Software Office
Each UofT email account is registered as a user in the Office Online portal for UofT. The portal should recognize the user's status (student / staff / faculty) and may adjust accordingly what exact product selection is offered.