I have just learned on my own. I read forums, babypips is a good one for learning. I don't think there is much value in forex courses - you might as well save your money for trading (use the money when you actually put what you learn into practice).
I have paid for things in the past and regretted it. You need to ask: if they are charging 'this much', how much are they making? I think those that charge big money are not making money from trading but from the materials or courses they sell.
But it is up to you: it's like learning a language - you can have formal education, but if you just move to that country and immerse yourself in the language you will learn better (I think). Formal education can keep you from making the mistakes you need to learn from.
The internet is a plethora of knowledge... you can learn anything you want just from the internet (well, I guess 'almost' anything). 😉