I can't really answer where I learned this stuff. I got interested in typed functional programming languages and one thing just led to another. I accumulated my knowledge from various places. For example, I first heared about the Curry-Howard correspondence from a page on the Haskell Wiki, but at the time, I had to go to its Wikipedia article to understand it.

I learn type theory from reading on the Internet. My father is a programmer, but he mainly uses C++, so he wouldn't know type theory.

To be honest, I probably wouldn't have learned about type theory if it weren't for the Advanced Topics subculture. My first exposure to programming was with Scratch, and on the Scratch "Advanced Topics" forum (ATs), there is a subculture of people (ATers) who are more knowledgeable about programming than the average user and enjoy pushing Scratch to its limits. (I guess you could say that the ATers are hackers.) One of my friends from the ATs is interested in programming language stuff, and many people there are Lisp hackers. So, the poeple in the ATs are probably responsible for stimulating my curiosity and directing me towards functional programming and PL theory. However, I wouldn't say that I learned type theory from the ATs.

Oh yeah, I also learn type theory from people on the Fediverse (the federated social network that Mastodon uses), as there are people there who are knowleadgable about type theory.