You can access the page for changing agent permissions by clicking on the "Permissions" link under "ADMIN -> Agents" in the side menu.

To explain agent permissions, we should explain "Departments" first. By default, two different departments are created when you sign-up to Helpviser: "Support" and "Marketing". You can add or remove your own departments from the menu shown below:

In the permissions page, you can see many checkboxes related to different features in Helpviser and their permissions for different departments. If you add a new department, the new department will be visible on this "Permissions" page and you can set different permissions to your new department as well:

You can check or uncheck any box depending on whether you want your staff in a specific department can view or add / edit any specific feature.
Note: Agents who have been set admin privileges can see all the pages and use all the features in your portal regardless of their department and the permission settings of their department.