They would normally drink every 3 to 4hrs. If he’s always hungry before that or cry for more milk after feed maybe it’s time to increase. My baby just turned 4 mths. Was stucked at 130ml for quite long till recently he cry for more milk aft every feed. So i made more milk n monitor his intake for few feeds to see how much is enough for him. At 3mths he was 6.3kg and from ard 3.5mths onwards he’s drinking 160ml. Hope this helps.
if he drink formula milk think just follow the formula tin, if is breastfeeding by bottle theres a link for u to calculate https://www.verywellfamily.com/how-much-breast-milk-should-i-put-in-a-bottle-431802#:~:text=Take%20your%20baby's%20weight%20in,in%20a%2024-hour%20period.