I read some finance textbook when I was just starting out, I think it was "introduction to derivatives and risk management". That helped too. It's a good, gentle introduction to derivatives and you can skip most of it unless you want to work for an investment bank.
I think the best way to learn is to just watch stocks overtime, and read up on the news relevant to them. That's really why I play with options, it keeps me plugged into following the movements of a bunch of different stocks, so I learn a lot about what makes them behave in certain ways. Definitely stay away from paid classes on investing or trading, those are almost all scams - if a "successful trader" has to teach paid classes they're not actually successful. And re: my strategy of trying to identify short term movements that make something under/over-valued and hoping it will correct, just realize that sometimes the market can stay irrational longer than you can remain solvent, and sometimes you just need to take the loss and get out.
One more thing I forgot. When I refer to "news" I mean real news. A lot of financial news websites are complete bot-written vacuous garbage. Real news is things like deals happening or falling through, large orders, interest rates, lawsuits, recalls, earnings, trade deals, etc.