Aye, you wrote that right.
Welcome! I signed up for a similar reason, though we used Nakama in class. If you want another workbook to practice in, you might try looking into Japanese for Busy People, and for the grammar, I found the Dictionary of Japanese Grammar to be a big help.
The thing about English grammar is that you know perfectly well how it works – you’ve been using it all your life. You just couldn’t really explain it, and don’t really know all the technical terms, because you learnt to use it pretty much just by using it. That’s probably the case for anyone aside from professional linguists. When you learn a second language, though, you’re explicitly told exactly how the grammar works.