Newborns are wired to suckle 24/7 as a reflex.
Try not to confuse the reflex with hunger. Hunger is a learned feeling, a desire to feel better if an emty stomach sends the message. If baby has just eaten, the stomach is not sending that message, but baby may accept a feed for comfort if offered. Breast fed stomachs can empty every 2 hours, formula
taked longer. Newborns grow fast and eat often.