As I said (iirc irl in the confusing data dump about the game), IIRC the game introduces concepts very gradually over time, and you can pretty much leisurely follow the storyline and get introduced to new gameplay concepts slowly. Ignore 99% of what we've said about the game so far and you should be fine
Just know that it's definitely an MMO, so its gameplay is a bit er, different from games you're familiar with. It's kind of an unnaturally controlled 3rd person game, where one half is moving your character around (you get moving / strafing and pointing your character in a direction), the other fighting (which is like err, 'enable auto attacks' which is usually automagic, and triggering abilities at a rate of approx. 1 per second).
that probably makes no sense. Go play it for like an hour; they recently announced they were going to make the demo unlimited, so it's basically a free to play game until lvl 35 (iirc).