What training did Yuri Gagarin have to do?

Answer 1

Not very much. He didn't actually pilot his Vostok 1 spacecraft when he became the first man in space. His participation in the mission was as a passenger only. He carried along with him an envelope with detailed instructions on what to do should anything go wrong during his flight. His training was basically emergency training, which took a lot less time than the Americans, who trained their astronauts to actually pilot the spacecrafts they flew in.