There was no period after his presidency, he was assassinated before his term ended.
Timeline of the presidency of John F. Kennedy was created in 1961.
Timeline of the presidency of John F. Kennedy died on 1963-11-22.
Timeline of the presidency of John F. Kennedy was born on 1917-05-29.
He was assassinated
He left the presidency because he died.
John F. Kennedy was assassinated (killed) during his presidency. So, there was no "after serving" for him.
before presidency John F Kennedy was a journalist but it was only for a short time.
None he was shot
New Frontier was the term he used for his program. Camelot was also used to describe the Kennedy presidency.
The "New Frontier"
The mafia.
bay of pigs