What can I expect in an appointment with an ent?

Depends. At the least, you can expect the doctor to obtain a history of the problem for which you are seeing him/her. You'll also have a physical exam of some sort, probably just of the head and neck region. What happens after that depends on your presenting symptoms and what the doctor finds during the exam.
Complete exam. You can expect a complete head and neck exam. For the ear exam, a microscope may be used. For the nasal and throat exam, you may have a telescopic camera exam to look inside. If you have hearing loss or ringing in the ear, you may also expect to get a hearing test during your exam.