When a Project Manager logs in, they will have access to a Project and Project Resources menu in the sidebar as well as menu items that Linguists have access to. However, the Project Resources that a Project Manager has access to depends on if they are a Full PM or a Vendor PM.
Note that the Community menu is not available to a Project Manager. They cannot create or manage users or adjust community settings. If a PM needs options available on the Community menu, they must be granted the Community Admin role.