(covers information from Vanguard universe)
this article was thought of and created by Maximus
The Flag Bridge is that part of a flagship of Starfleet where Flag Officers-in-Command hold station and where he/she and his/her staff direct fleet or task force operations, plan fleet movements and draw up orders. It is the nerve center of the fleet or task force. It is where coordination between fleet or task force elements and planning for their operations are done It is manned by the staff of the FOIC.
Onboard flagships of Starfleet , especially those classified as Fleet Carriers and Heavy Battleships, Flag Bridges are found in the rear half portion of the Main Bridge; the front half portion being the Navigation Bridge, where the ship's Commanding Officer and his bridge staff hold station. The Flag Bridge is slightly elevated from the Navigation Bridge and is separated from it by a transparent wall, which enables the FOIC to look at the large view screen of the navigation bridge below. Passageways on the port and starboard sides are present, allowing for easy access between the two halves of the Main Bridge. It is a much expanded version of the Situation Room found at the aft portion of Midway-class starships
The Fleet Operations Table, a large rectangular multi-station console is located at the center of the Flag Bridge, which can project above it a three-dimensional image of any region in space that the FOIC would like to view. This console functions similarly to that of the main workstation of Astrometrics or Stellar Cartography.
The Flag Chair, where the FOIC sits, is located between the Fleet Operations Table and the transparent wall dividing the Flag Bridge from the Navigation Bridge. It can swivel around so that the FOIC can face the Navigation Bridge.