Level 1: What should a three-month-old baby eat? At three months of age, the baby\’s gastrointestinal function begins to gradually develop, and complementary foods need to be gradually introduced at this time. But since your baby\’s digestion is not mature enough, you need to pay attention to food selection and cooking methods. First of all, you can feed your baby some liquid foods such as rice noodles, millet porridge, and porridge. These foods are easy to digest and will not cause excessive burden on the baby\’s gastrointestinal tract.