There is an old joke where a student asks a teacher, “can I go to the bathroom,” and the teacher responds with, “I don’t know, can you?” This joke illustrates the common misuse of the words can and may when asking a question.
The word “can” is used when you are talking about an ability. Some examples are:
I don’t know if I can do it.
Can you climb to the top?
The word “may” is used when you’re talking about giving or getting permission to do something. Some examples are:
May I go to the restroom?
May I pet your new puppy?