Hello! Girls, could you please tell me what to feed a child of 5 years…

Hello! Girls, could you please tell me what to feed a child of 5 years old? She had vomiting three times, has pain in her stomach, went to see a pediatrician who prescribed only intravenous fluids. I want to put her on a diet and give her bismuth subsalicylate for the stomach pain, she also has allergic bronchitis, she was prescribed Altai syrup by the doctor.