I have been sick over 2 monthsi can't get rid of cough and yellow phlegm. i'm not a smoker. what can i do?

Have you seen doctor: If you have had cough and purulent sputum for over 2 months, you have some kind of serious respiratory infection. While smokers certainly get more of these, non-smokers can get any kind of infection as well. Your doctor needs to examine you, take a full history, probably get samples of your sputum for testing and probably a Chest Xray or other imaging studies of your lungs. See your doc NOW.