It should be "May I ask you a question?" because you are asking permission to do so. will you make a question "how to write a question" cause i dont know how
You can ask a question and answer your own question. You can then ask another question. If you ask a question that has already been answered you will see that in the asking process.
Yes, it is. Furthermore,it would also have been a question if you had thought of asking a question that is a question related to a question mentioning a question.