I am only thirteen but my mom has a baby that I am very knowledgeable about. What I know for surevisbthat you need to feed the baby at regular feeding. Times when you eat,like lunch breakfast SO on. then,when she starts to get older,you feed at that same rate but you need to start feeding less formula. if this helps then good,but I'm only taking off the prospective that I am left with when I watch a child.
Start solid food, like baby food or baby cereal, very slowly. Try a tablespoon at one feeding per day. U want to make sure she does not have ANY bad reaction, like excess crying, gas, or a rash. May mean an allergy