Physicists have uncovered a hidden third form of magnetism that challenges more than 100 years of established physics. Called altermagnetism, the discovery could transform future computing and electronics while opening an entirely new frontier in quantum research.
I’d just get a used electromagnetism textbook that’s only a few years old.
However, that’s going to assume you already have a pretty solid base understanding of physics, you can’t really just jump straight to electromagnetism. You could try, but it’s likely gonna be like reading a different language.
Maybe look into classes at a local community college?