Projects, streams, and floods must be created in that order; that is, it is not possible to create a flood without first creating a project, then a stream, and then a flood. When you first sign up to a new account with Flood, a default project will be created for you.
When a project is created by an account manager or an organization manager at the organization level, they will be asked to assign it to a team. They'll then be asked whether to give the team Admin, Read, or Write permissions.
When your team manager creates a project for your team (on the team level), your team will automatically receive Admin permissions.
Either way, all members of any one team will share the same permissions with regards to a project.