Demand feeding or time feeding which one is correct? if baby latch more than 20 mins we have to stop them? How often I should feed her

A. By the time your baby is 1–2 months old, he or she probably will nurse 7–9 times a day. In the first few weeks of life, breastfeeding should be "on demand" (when your baby is hungry), which is about every 1-1/2 to 3 hours. As newborns get older, they'll nurse less often, and may have a more predictable schedule.