The "glass" is plastic. No it, of itself,can't be replaced. It is part of the whole, so the enter headlight assembly must be replaced as an unit. HOWEVER, that is not necessary. They headlights are easily cleaned and polished. Most auto parts stores sell kits for the job and there is even a method to clean the inside of the headlight assembly, but that requires the assembly be removed from the car. Use the search box at the top right of the forum page to search. You will find many threads on the subject.
If that is the only problem you have. It is a minor affair easily brought back to like new appearance.