Breast milk is digested in 1.5hrs, so really anything over that time I would offer a feed.
At the beginning, feed as frequently as you feel baby wants it. It will space out in time, but you need to establish your supply first.
And all babies are different. DS1 wanted more feeds in a 24hr period, DS2 wanted a looong cluster feed. Once they both spaced themselves out, I still couldn't get DS2 to go 3hrs until he started on solids. Turns out that he eats an absolute ton, so that's why!