You can usually find a $10 antigen test at most pharmacies, don’t go inside most smaller pharmacies will take it out to you or use the drive through. If she’s positive and fits the right criteria then she can get paxlovid with a free ma telehealth appointment (meds are still free as well I believe).

Other than that Advil or Tylenol, fluids and rest. It sucks. https://www.mass.gov/info-details/treatments-for-covid-19