Short answers, pulled from the story.
Germany's unconditional surrender was signed at 02:41 on the 7th of May 1945, at SHAEF headquarters in Reims, France, by General Alfred Jodl. A second signing ceremony took place in Berlin on the 8th of May, and that date is celebrated across Europe as Victory in Europe Day. Russia marks the 9th of May as Victory Day because the end of operations occurred after midnight Moscow Time.
General Alfred Jodl, chief-of-staff of the German Armed Forces High Command, signed the first surrender document in Reims on the 7th of May 1945. The following day, Field Marshal Wilhelm Keitel and other German OKW representatives signed a second document in Karlshorst, Berlin, in the presence of Marshal Georgy Zhukov. The building used for the Berlin ceremony now houses the Museum Berlin-Karlshorst.
Adolf Hitler died by suicide in his Führerbunker in Berlin on the 30th of April 1945, along with Eva Braun, whom he had married less than forty hours earlier. In his will, Hitler dismissed both Göring and Himmler for attempting to seize power and appointed Karl Dönitz as Reichspräsident and Joseph Goebbels as Chancellor. Goebbels also died by suicide the next day.
Combat continued for weeks after Germany's formal surrender on the 7th of May 1945. The Battle of Odžak in Yugoslavia ended on the 25th of May, and a German unit on Svalbard, having lost radio contact, did not surrender until the 6th of September 1945, when they gave themselves up to Norwegian seal hunters. The Red Army formally halted all offensives in Europe on the 13th of May 1945.
Western Allied forces alone captured 1,500,000 prisoners on the Western Front in April 1945. At least 120,000 more German troops were captured in Italy during the same month, and over 800,000 soldiers surrendered on the Eastern Front in the three to four months leading up to the end of April. Nearly 1,000,000 men in Italy and Austria surrendered on the 2nd of May.
"The full authority of a sovereign state" was granted to the Federal Republic of Germany on the 5th of May 1955 under the Bonn-Paris conventions. Full legal closure came with the Treaty on the Final Settlement with Respect to Germany, signed after the 1990 reunification, which came into force on the 15th of March 1991 and saw all four Allied powers renounce their remaining special rights over Germany and Berlin.