This article shows the steps on how to Add Users to SharePoint Online. The document is broken into two sections of using the Main Tees Portal and using the Individual SharePoint research sub-TEES site.
Main
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TEES Portal
Select Site settings:
Select “People and groups” under Users and Permissions
Select “New”, and then “Add Users”
Type in the names or email addresses of the users you would like to add, then include a personal message for the invite to the site if you so desire.
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