Oof, I'm sorry the level select screen wasn't more clear. That part was not as polished as I would have liked. I've since posted an updated version on my personal website that tries to improve it by making a connecting line between the levels, kind of like in old school mario games, although even then, it could still probably be a little more clear. I also improved the white bullet spawn rates on a lot of the levels, which makes it go a bit faster.
https://jasmine.games/#/games/angels-odyssey