I understand you are concerned about your father. For temporary relief, he can take paracetamol to help reduce the fever and body pain. To prevent dehydration from vomiting, please encourage him to sip oral rehydration salts (ORS) or water slowly. Avoid giving him pain relievers like ibuprofen, as they can further irritate his stomach. Because the combination of stomach pain, fever, and vomiting can indicate an underlying infection or issue, it is highly recommended to consult a doctor for a proper diagnosis and tailored prescription. If he cannot keep fluids down or has severe pain, seek medical care promptly.