2 Jim Lovell and Fred Haise
3 astronauts on Apollo 13 one of them did not go up but he went up on Apollo 14.
The question is not clear, there were three astronauts at a time in a Apollo mission , and there were 11 Apollo missions.
The CSM (Command Module) had one main engine. The LM (Lunar Module) had a Descent engine and an Ascent engine. Both the CSM and the LM had some tiny steering rockets. These would not be considered...
James Lovell and Fred W. Haise are retired astronauts, and astronaut Jack Swigert has died of bone marrow cancer.