S.H.
You just feed on-demand, 24/7, day and night.... for the 1st year at least.
6 months will be coming up and that is also a 'growth-spurt' time...and a baby will then become hungrier and more often. Normal.
For the 1st year.... breastmilk or Formula, is a baby's PRIMARY source of nutrition... NOT solids and NOT other liquids.
You need to feed on-demand... because everyday, a baby's intake needs and appetite varies. Feeding on a "schedule" is not good. It does NOT address a baby's varying appetites nor their growth-spurts and intake increases. And you cannot arbitrarily decide 'when' to feed a baby...because they don't feed according to a schedule. Nor can you predict when they will be hungry or how much they will drink...
Is he drinking breastmilk or Formula? Regardless, a baby needs to feed on-demand....
For spit-up... they should be burping him.... and keep him upright after feedings.
Also though, some babies just spit-up a lot. My son was like that and he was in the 95th percentiles.... and he had a GINORMOUS appetite and fed a lot... and often... and more so during growth-spurts.
Growth-spurts in babies, occurs about every 3 months...
all the best,
Susan