The correct spelling of the phrase "am business" in Standard English is "I'm in business". The contraction "I'm" is short for "I am", and the preposition "in" is used to indicate that the speaker is a participant or involved in some way. The word "business" is pronounced /ˈbɪznəs/ with a stressed first syllable and a voiced 'z' sound. Proper spelling and pronunciation are important for effective communication, whether in casual conversation or professional settings.