Thanks everyone for the warm welcome and helpful information.
I'm still a novice, but I do have a vague knowledge of everything you mentioned. Like I said, I've watched streams for several years and have kind of organically picked up on things. I'm still at the stage where when I'm actually in a match I start to panic and the button mashing begins. I presume this is something that happens with everyone when they start, because people I've played in casual matches in fighting games do similar things.