Irabeth (profile number 2 here) - In the post Cataclysmic world which Irabeth was from there are essentially two forms of education. In smaller ‘towns’ education is a communal effort with everyone pitching in what information they can during whatever time they can spare. Much of this is practical skills and information (passed down from the previous generation) about what the world used to be like before the Cataclysm. The only formal education is that provided by the Hegemony, which is primarily focused on training children for positions within the Hegemony in later life.
Irabeth was from one of the smaller communities (a lack of formal Hegemony education was one of the reasons she got the shitty assignment of Custodian) mostly notable for the extensive farm chambers. Irabeth received a pretty thorough education in farming, scavenging (though she never got to see the surface personally) and history from her great aunt who spoke about magic which such wonder.
Phere - Phere grew up on the street with her big brother Tehra. She was an inquisitive child, very keen to understand how things worked, and likewise how people worked. Tehra did his best to answer whatever questions she had about the world, given that he was necessarily self-taught, he was perhaps not the most reliable source of information. Whenever possible he would steal books from the court library or bombard the small handful of professors that weren’t outright hostile to him with questions in the hope of getting some answers he could bring back to his sister.
When Phere started showing a proficiency for magic and a desire to learn more Tehra knew that this was not something he could not teach her himself. He started doing favours (often elaborate and of an ethically dubious nature) for court archmage Esemyne in exchange for her time spent teaching Phere. Eventually seeing the potentially inherent in the young girl Esemyne took Phere as a sort of unofficial apprentice, teaching her not only magic but all about the world and how to best wrest control of it.
Nameless - Nameless first started formal education at age ten at the Raxucorp Boarding House for Disadvantaged Youths. She was said to have a Bad Attitude and be simply Unwilling To Learn. Later that year, for no obvious reason, she was one of a handful of kids scouted to the Raxucorp School For Gifted Young Minds. She lasted almost a month there before running away. She never sought further education, moving pretty quickly into various forms of temporary employment.