Short answers, pulled from the story.
Prince Georgy Lvov took the helm of a new Provisional Government on the 2nd of March 1917. This date marked the moment Emperor Nicholas II abdicated his throne after the February Revolution.
Alexander Kerensky signed a decree establishing the Russian Democratic Federative Republic on the 1st of September 1917. He served as Minister-Chairman when he issued this proclamation alongside Alexander Zarudny, the Minister of Justice.
The Bolsheviks seized power by force on the 7th of November 1917 and dissolved both the Provisional Government and the Provisional Council immediately. The Russian Republic ceased its effective existence following this violent takeover.
On the 18th of January 1918, the Constituent Assembly issued a decree proclaiming Russia a democratic federal republic. They named the nation the Russian Democratic Federative Republic in their official document before the Bolsheviks dissolved it the next day.
The Bolsheviks proclaimed the creation of the Russian Soviet Republic on the 25th of January 1918. This declaration marked the end of the de jure existence of the previous Russian Republic.