What does je n'adore pas mean?

This would not be a complete sentence, but it means "I do not adore".
"Je" is a subject pronoun meaning "I", and adore is the first person/third person conjugation of "adorer" meaning "to adore". "Ne pas" placed around a conjugated verb negates the verb, though in this case because "adore" begins with a vowel, the "ne" become just "n'" so that the sentence flows better.