I can't seem to find the fortune point max for characters in the tome of adventure or main rulebook which leads me to believe it's three from when drawn at the start of each session. If some could point out what this is, how it's derived, and in which book the help is appreciated.

Yeah, istm you start with 3 and you have an implicit max of 3, but it doesn't state that explicitly anywhere I can find.

On WFRP 16, Paragraph 2, it says:

When this refresh occurs (talking about refreshing fortune from the party sheet), each party member who currently has few than his maximum number of fortune points may claim one <snip>

Then again, in the same paragraph:

A character that already has his maximum number of fortune points cannot claim a fortune token <snip>

I'm pretty sure 3 is the implied maximum number of fortune points. It refreshes to max at the beginning of each session.