Thanks for posting your question in the Microsoft Q&A forum.
You'll need to contact McGill's IT support or the department responsible for Workday access.
Confirm with the IT support or your department that you should have access to Workday. There might be a process for requesting access if it's not automatically granted to all students.
The IT support team will need to either add you to the appropriate group or directly assign your account access to the Workday application in Azure AD
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