Hi Dhairya

i don't think you need a tenant structure as reports for course completion can be setup to only display the direct or indirect reports for the user viewing the report.

Have a look at the report source 'Manager course completion status overview' and the Content tab on how to restrict the display of records based on the user viewing the report.

Managers can be assigned to users manually through the profile and job assignment or through importing a file with job assignments

regards