When we use an auxiliary verb (to do) for questions, it handles the conjugation as well. So we say "He has X keys", but the question is "How many keys DOES he HAVE?" Also, please remember to write "I" as a capital letter. "How can I say...?" Writing "i" is a mistake.

The correct English is "How many keys does he have?" You would use has when the person is the object of the sentence and talking about the person possessing something. For example "He has many keys"

...doES he have? he haS he doESn't have