Explanation in general is pretty much complete, although there are several improvements that can be made on the video.
(Personal Opinion) - I think newer player will find it hard to tell the skin for the drum layout (dons and kats) in your video (at least that's the case for me at first glance because the colors for the d and k at the drum layouts are the same and they look very small).
2:26 you're talking about finishers, but showing sliders instead. It's the same case with the spinner
2:35 Sliders don't give you HP,they just give you extra score
4:03 the kddk colors are reversed
(Personal opinion) - As to where to look is pretty much correct, with the addition that on higher bpm and/or higher sv, you'll need to look a bit to the right, assuming you don't use mods like Hidden or Flashlight.
(More Personal Opinion) - As to where to start, avoid playing convert. Don't be like me. I spent the first 6 months playing convert only and it was hell.
