I have throat infection each2-3 month. This time even though im taking antibiotics, it's still bad and my mouth soo bitter at night. I'm a smoker?

Quit smoking. Smoking cigarettes or exposure to smoke can trigger persistent sore throats. Your first step is to talk to your PCP about which medication would be best for you.
Tonsils? Still have your tonsils? You may be having recurrent tonsillitis. See an ENT doc to assess your condition.