did he walk on any planetary body?
Yes, he was the  first person to walk on the Moon.
Neil Armstrong
Neil Alden Armstrong (August 5, 1930 – August 25, 2012) was an American astronaut and aeronautical engineer, and the first person to walk on the Moon. He was also a naval aviator, test pilot, and university professor.

what was the general purpose of the apollo missions landing the  humans on the Moon when was it launched? 1968 which organization launched it? National Aeronautics and Space Administration can you name any of its used spacecrafts? Lunar Excursion Module , command and service module any astronaut who took part in its program? Neil Armstrong, Michael Collins and Buzz Aldrin has this first person been to navy? Yes, he was also a naval aviator. which other space program was he a part other than the above one? National Advisory Committee for Aeronautics (NACA)
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Neil Armstrong [SEP] Introduction
During this mission with pilot David Scott, he performed the first docking of two spacecraft; the mission was aborted after Armstrong used some of his re-entry control fuel to stabilize a dangerous roll caused by a stuck thruster. During training for Armstrong's second and last spaceflight as commander of Apollo 11, he had to eject from the Lunar Landing Research Vehicle moments before a crash.