Maybe and may be are almost identical, but that little space makes a big difference that may be confused by native speakers. Maybe this lesson will help you understand.
Maybe is an adverb that means "possibly, perhaps." It is used with verbs.
It can also be a response to a question.
May be is made up of two verbs (the helping verb may and the infinitive be) which together refer to a possibility. They are not used with another verb.
The Bottom Line
The meanings of maybe and may be are similar; the different uses are grammatical. Maybe must be used with or in reponse to a verb, whereas may be is a set of two verbs.
Generally speaking, if there’s a verb in the clause, if you’re tacking it on to the end of a sentence, or if you’re responding to a question, maybe is the correct choice. Otherwise, may be may be your best bet.