please some tips of my baby she's 3 years old but her weight is not gain what I do for her weight gain

A. To help child gain weight, include fat and protein rich foods like potato, rice, pumpkin, sweet potato, eggs, chicken, fish, legumes, ghee, milkshakes with dry fruits, banana, avocado, paneer and 550-650 ml milk everyday including variety of fluids like water, fresh juices, curd, buttermilk and coconut water. Feed 3 main meals and 2-3 times healthy snacks and avoid giving sweet, fried and packaged foods.