1) babypips.com (in order to learn the basics of FOREX trading)
The site can really be relied upon to learn about forex trade. I used to go through it while trying to learn too. It is useful for newbies because it lessons are made simple that you will understand all aspect of forex trade. You can also use its teaching to build or support your knowledge on cryptocurrency trading too.
Forex trading and bitcoin trading do have some differences, there are a lot of common stuff as well but there is a lot of differences as well. First of all forex is not really changing that much depending on some guy selling, it is trillions of dollars worth market that has so much volume every single day that, one person can't ruin all of USD/EUR market for example, it is going to be basically the same if you just sell a billion dollars worth of it, it is not going to change at all.
However in crypto market if you sell a billion dollars worth of bitcoin you are going to cripple the market and price will plummet. That kind of differences are stuff you learn by time, you have to just gain experience and see those things and act accordingly but just be patient and you will get there, it might take some time but you will get there.