At 10 months, it is generally recommended to continue using breastmilk, formula, or breastmilk-based substitutes, as cow's milk should only be introduced as a primary drink after 12 months. For calcium and nutrition, you can incorporate cow's milk into cooked dishes like ragi porridge, pancakes, or upma. To ensure your baby gets enough nutrition, focus on nutrient-dense meals like ragi-based preparations combined with nuts and dates (if introduced safely) and follow your pediatrician's guidance on the best milk substitutes until they reach the one-year mark.