"A one-year-old girl, if you take her away from breastfeeding, should …

"A one-year-old girl, if you take her away from breastfeeding, should you introduce formula? I think it will be fine during the day, but at night, maybe because she often cries and asks for a babysitter. ? So, please share your experience in short, how many days did you struggle and after what changed in the baby's sleep ? If you do introduce formula, which is best? Regardless of price. By composition, so that there are no constipation and etc."