When you invite someone to your Project.co account you specify thier email address, role and group. You don't specify any other personal information.
Then, when that user logs in to their account for the first time they can specify their name and add a profile photo. It's not possoble for you to edit a users personal information such as their name or photo because they may access multiple accounts on Project.co.
However you can edit their role and groups.
To do this, navigate to the people page and find the user you want to edit. Then click the "Options" button on the users row and select "View Person".
From this page you can click on the "Options" button and select "Edit Person".
From here you can update the users role and groups.