Why do i have to spit out phelgm every morning? is this normal? how do i prevent it from happening?

Phlegm: Might be from allergies (molds, mildews, pet dander, dust mites, etc), cigarette smoking or 2nd-hand smoke, fumes (plastics, new carpet, paint, perfume/cologne, laundry detergent, fabric softener). Stop smoking (if u do). Nasal saline spray or nasal steroid (nasonex, etc), vacuum with hepa filter, air filter with hepa filter, clean furnace filters, treat moldy areas. See fp/allergist if more help.

Allergies : Allergies and post nasal drip is the most common reason. The easiest thing to try first is an over the counter version of something like zyrtec . If that does not work you will need to see your dr as you may require a prescription