A 28-year-old woman from rural Maharashtra presents with fatigue and dyspnea on exertion for 6 months. On examination, she has pallor and angular cheilitis. Her hemoglobin is 7.2 g/dL with MCV 62 fL and serum ferritin 8 ng/mL. Peripheral blood smear shows microcytic hypochromic RBCs with occasional target cells. What is the most appropriate next step in management?