Short answers, pulled from the story.
The Transcaucasian Socialist Federative Soviet Republic was officially created on the 13th of December 1922. This federation transformed from the earlier Federative Union of Socialist Soviet Republics of Transcaucasia which had been established on the 12th of March 1922.
Mamia Orakhelashvili served as the first chairman of the Council of People's Commissars from March to December 1922. Polikarp Mdivani represented Georgia concurrently during those initial months while Nariman Narimanov held leadership positions for Azerbaijan until 1925.
The Transcaucasian Socialist Federative Soviet Republic dissolved in December 1936 following the adoption of the 1936 Soviet Constitution. Its constituent republics Georgia, Armenia, and Azerbaijan each gained separate SSR designation after the federation ended.
Tbilisi served as the capital of the new republic when it was formed in 1922. This city functioned as the administrative center for the unified state that existed for fourteen years before its dissolution.
Abkhazia's republican status was downgraded to Autonomous Soviet Socialist Republic within the Georgian SSR on the 19th of February 1931. It had previously been a treaty republic under the Georgian SSR since signing an alliance agreement on the 16th of December 1921.