The words "perhaps" and "maybe" are used equally when answering questions.
For example, when someone asks you, "are you coming for supper?", you could use either word in reply.
Both words mean "it is capable of happening" or "likely to happen".
The word "maybe" sounds more casual.
The word "perhaps" sound a little more formal.
For example, saying "maybe I will go for a walk" sounds like a conversation between friends.
"Perhaps I will join you" sounds like a conversation between business associates.
Hope this helps