how much ml milk my 3 1/2 month should take and was a preterm baby?

A. A 3-month-old needs to eat about 4 to 6 ounces of breast milk or formula every 3 to 4 hours. 1 Since all babies are different, some babies will eat a little more or a bit less than this. When your baby is 3 months old, they have reached an important milestone—they are no longer considered a newborn