In this letter Kennedy restates Khrushchev’s proposals. Does Kennedy include everything Khrushchev proposed? If not, why might have he left something out?

No, because Krushev wanted the USA to be out of Turkey. Kennedy wanted the Soviet Union to take its missiles out of Cuba and Kennedy's letter there is no a thing about Turkey because Kennedy was a hard and savvy negotiator and he did not want to give up American interests in Europe and at the same time he was really concerned with the security of the nation.
Khrushchev proposed that Kennedy remove his missiles if he publicly stated that he would never invade Cuba.
No, Kennedy does not include everything that Khrushchev proposed.
Therefore, Kennedy concluded his letter by stating that the continuation of the Cuban Crisis would pose a "severe threat to world peace."
For more information about the letters, refer to the link below
https://brainly.com/question/7265857