To assign a user to a project you must have the role of Account Administrator. Each user that is added to a project is assigned a Project role which provides them with specific Project permissions.
Refer to our page about managing users for a full description of the roles and their capabilities.
From a Project dashboard, select Users
Add a user from the Select Users dropdown, choose a project role (Author, Administrator or User) from the Role dropdown, and click Ok.
Use x remove to remove a User from a Project.
Now consider how you will enable access to data in your Project, there is some background information in the page Agent - Architecture for Data Access