He was God and I assume that He could read, however, that is just an assumption. I Jesus time, there were learned people who could read, but the general population relied on those people to read to them and interpret what the written messages were...The VAST majority of the people couldn't read and perhaps Jesus felt no need to do so. His parents were, as a tradesmans family, possible educated and thus could teach Jesus to read....but who knows???
That simply isn't true.
Your average Hebrew child was taught his aleph-bet by his mother, and wrote Torah at his father's knee before he was a teen... By the teen years, they had Torah memorized. If they excelled at such, they went on to school to learn the entire Tanakh, with the hopes of sitting at the feet of a rabbi. Every man wrote himself a Torah, as commanded in Torah.
Even base Hebrew slaves could read, and write as proven on the walls of mines in the Sinai, and upon the walls of Pompeii.
Literacy was widely practiced except where the Roman church seemed to be... funny, that.