Short answers, pulled from the story.
The Grand Council of Fascism voted on the 25th of July 1943 to end Benito Mussolini's sixteen-year rule. Dino Grandi proposed restoring direct political control to King Victor Emmanuel III and the motion passed that evening.
General Giuseppe Castellano signed the armistice text alongside General Walter Bedell Smith at 14:00 on the 3rd of September 1943. The ceremony took place inside the Fairfield military camp located in Cassibile, Sicily.
German bombers attacked the sailing fleet off Sardinia without air cover and sank the Roma with nearly 1,400 men lost. Guided bombs struck the ships causing damage while most remaining ships reached North Africa safely.
Badoglio and Eisenhower signed the longer version of the armistice aboard HMS Nelson at Malta on the 29th of September 1943. This document included provisions for handing over Mussolini and his Fascist officials to United Nations forces.
German forces executed Operation Achse immediately after learning of the Italian surrender intent and attacked Italian troops across Italy, southern France, Greece, Yugoslavia, and the Dodecanese islands. They occupied all remaining Italian territory except Sardinia and parts of Apulia from the 8th to the 12th of September.