Do these mean the same?: Not exactly. Not quite. Not really.
한국어로는 다음의 표현에 해당되는 듯 싶네요. Not exactly꼭 그런 건 아니고. Not quite. 완전히는 아니고. Not really 그런 건 아니고/(아니) 별로.Would you like to go to the movies? 영화 보러 가지 않을래요? Not really. 아니 별로요Merriam Webster Learner's Dictionary에 나온 quite의 뜻풀이가 'completely or entirely'로 나오고 예문이 다음과 같네요.
“Are you quite finished?” “Not quite.”
(다 끝냈니? 다는 아니야.)not exactly informal1 — used in speech as a mild way of saying “no” especially to indicate that what someone has said is not completely correct or true(비격식 대화에서 no를 온화한 방법으로 말하기 위해 쓰인다. 특히 누군가가 말한 게 완전히 맞거나 진실은 아니라고 말하기 위해 쓰인다.
“He's your boss, isn't he?” “Not exactly.”
그는 너의 보스지? 꼭 그런 건 아니고.
“Did everything go the way you planned it?” “Not exactly.” 모든 게 네가 계획한대로 됐니? 완전히는 아니야(아니고).

Question

Do these mean the same?: Not exactly.  Not quite.  Not really.
한국어로는  다음의 표현에 해당되는 듯 싶네요. Not exactly꼭 그런 건 아니고. Not quite. 완전히는 아니고. Not really 그런 건 아니고/(아니) 별로.Would you like to go to the movies? 영화 보러 가지 않을래요? Not really. 아니 별로요Merriam Webster Learner's Dictionary에 나온 quite의 뜻풀이가 'completely or entirely'로 나오고 예문이 다음과 같네요.
   “Are you quite finished?” “Not quite.”
  (다 끝냈니? 다는 아니야.)not exactly informal1 — used in speech as a mild way of saying “no” especially to indicate that what someone has said is not completely correct or true(비격식 대화에서 no를 온화한 방법으로 말하기 위해 쓰인다. 특히 누군가가 말한 게 완전히 맞거나 진실은 아니라고 말하기 위해 쓰인다.
  “He's your boss, isn't he?” “Not exactly.”
그는 너의 보스지? 꼭 그런 건 아니고.
  “Did everything go the way you planned it?” “Not exactly.” 모든 게 네가 계획한대로 됐니? 완전히는 아니야(아니고).

Answer

The most natural answer(s) are given after the question:

-Would you like to go to the movies? 
--Not really. I don't really (truly) want to go to the movies.

-Are you quite finished? 
--Not quite. I am almost finished, but not quite.
--Not really. I am not really (truly) almost finished.
("Not exactly" could be used in some instances, but would not be as common.)

-He's your boss, isn't he? 
--Not exactly = Not really = Not quite. He is not my boss; he is something other than my boss.

-Did everything go the way you planned it?
--Not exactly = Not quite = Not really. Everything did not go the way I planned.

Note: in this last one, the "it" is not necessary in your sentence, at least in idiomatic usage.

Answer

With language, of course, everything is dependent on the context. But without any context given, I would say that
"Not exactly" and "not quite" are very similar. Perhaps "not quite" sounds a bit more negative than "not exactly".

Are these two chairs the same? Not quite. Not exactly.

Both say that the chairs are similar, but not precisely the same. "Not quite" is often used sarcastically to mean that the chairs are not at all the same, but you will hear "not exactly" used in that same sarcastic fashion.

Are these two chairs the same? Not really.

"Not really", on the other hand, seems to make much less of an assumption that the chairs are similar. They may be quite different indeed. "Not really" is often used as a less harsh way of simply saying "no".

Would you like to go to the movies? Not really.
That doesn't sound as dry as simply saying "no".

Answer

다 아주 비슷해요. 특히 not exactly랑 not quite는 거의 차이가없을정도에여. not really는 표준어라고 생각하시면될것같네여 은근히 귀찮음도 전달되고여