Andrej's answer is correct. As a general rule: kein goes with nouns, nicht with verbs. Ich habe keinen Apfel. Ich kann nicht schwimmen.

Weder noch. "Ich spiele nicht Gitarre." Außerdem heißt das "keine", "kine" gibt es nicht.

Andrej's answer is grammatically correct, but most native speakers would probably not put it that way, for the following reason: "Ich spiele nicht Gitarre" is ambiguous, - it doesn't tell you whether the speaker 1) is not playing the guitar right now (but maybe he/she is an excellent player) OR 2) can not play the guitar at all. For option 1, you'd better say "Ich spiele gerade nicht Gitarre". For option 2, you'd better say "Ich kann nicht Gitarre spielen" (I can't play the guitar).

Vielen Dank