To gain weight in a healthy way, focus on increasing your daily calorie intake with nutritious foods and combining it with regular strength training. Eat balanced meals that include carbohydrates (rice, roti), protein (dal, eggs, paneer, milk, curd), and healthy fats (nuts, peanut butter, ghee) in moderate amounts. Try to have 5–6 small meals a day instead of skipping meals, and include snacks like bananas, dry fruits, or smoothies made with milk, bananas, and nuts. Adding protein to every meal helps build muscle rather than just fat. Lightweight training or bodyweight exercises 3-4 times a week can further support healthy weight gain. Also, ensure good sleep and hydration. If you are not gaining weight despite eating well, consult a doctor or nutritionist to rule out any underlying health issues and get a personalised plan.