You can slowly increase his solid meals if he likes it but just make sure tt he still has milk for most feeds.
E.g
Early morning : milk
Breakfast: 3 to 4 tablespoons of rice cereal mixed with milk
Mid-morning :milk
Lunch: ¼ to ¾ bowl of solid food
Afternoon snack: milk
Dinner: ¼ to ¾ bowl of solid food
Evening snack: milk