6 week old formula fed baby sleeping times?

How long is your 6 week old baby sleeping ? I am formula feeding and my baby is waking up every 2 hours (days and nights) . I am so exhausted ! His pediatrician told us that we need to do 8 feedings within 24 hours , so every 2-3 hours. I see people saying that their 6 week old is sleeping like 7-8 hours a night . How is this possible ? First off my little man won’t sleep even 4 hours. ..second , is your pediatrician not recommending feedings every 2-3 hours? By the way, my baby is past his birth weight . I return to work in 6 weeks and I’m just worried that I’ll still be waking up every 2 hours at night and struggling at work during the day.

Added info: he’s getting 3-4 oz of formula during feedings