Short answers, pulled from the story.
The Prague offensive commenced on the 6th of May 1945 and concluded on the 11th of May 1945. Marshal Konev ordered the start date to be moved forward from the originally planned the 7th of May due to events in Prague.
Marshal Konev commanded the 1st Ukrainian Front which led the main thrust of the operation. The 2nd Ukrainian Front advanced from the southeast while the 4th Ukrainian Front operated further east toward Olomouc.
The Prague offensive destroyed Army Group Centre and parts of Army Group Ostmark which were the last large intact military formations of Germany. Almost nine hundred thousand German soldiers became prisoners of war or fugitives following the surrender.
Allied nations suffered eleven thousand nine hundred ninety-seven irrecoverable deaths plus forty thousand five hundred one wounded and sick totaling fifty-two thousand four hundred ninety-eight personnel losses. Material losses included three hundred seventy-three tanks and self-propelled guns alongside one thousand six artillery pieces and eighty aircraft.
Stalin ordered the start date moved forward because Czech insurgents gained control of a radio station and broadcast appeals for air support against German armored units. This development prompted Stalin to hasten the offensive to ensure Soviet presence in western Czechoslovakia when German troops surrendered.