Last Hope of Humanity... the UFP Exodus fleet
Star Fleet has three main branches:
Special Services Commandos -
In the Exodus Fleet, each branch has a commander. In addition, the Tech, Science, Engineering, Supply and Medical branches have commanders. However, the Fleet Commander is the Admiral of the Fleet and the Executive Office is the Marine Commander. The Medical Officer has the authority and command control to remove any fleet personnel, but cannot themselves command.
Star Fleet has various roles and command structures that include: Astronauts Science Engineering Tech Medical Marines Commandos
the Main Branches are: Command Executive Science Engineering Medical Tech Marine Corps Commandos Assault Force