Interesting combination of real graphics and stylistic art for the models. Along with the jazzy theme music and unconventional aspect ratio, makes the presentation quite unique.
First attempt: I immediately got caught in the collision shape and ejected from the tutorial level, falling into an endless pit. Had to refresh my page to get a new game going. Though did notice you'd noted that as a likely scenario in the tutorial, thus it may have been a good idea to throw in a restart function somewhere (or have plane colliders above and below the level that automatically restart the level if hit).
Second attempt: Game crashed and closed the Brave browser tab (first time that's ever happened) when I used Ctrl to slide in the tutorial level.
Third attempt: Tried on Opera, but it inadvertently closed the tab again. This prompted me to check the comments, and I saw shp's and JMC's explanations that Ctrl+W is what's closing the tabs. So looked for a download, but unfortunately there wasn't one.
Sympathetic to unforeseeable bugs, since in the midst of development, it's not even on the radar to know that basic input keys are going to conflict with a browser's shortcut keys.
The fix for this for future players: always be holding the W key. Letting go of it, and pressing Ctrl first, will trigger the browser's shortcut input.
Fourth attempt: When I got the game going, the level was fast-paced and very action-y! The speed jump of the crouch encourages a player to spam it, but the boost is what makes it so fun. Given that you've incredibly done this in 3D, I'd love a future level with twists and turns on the other axis. Perhaps even something that launches you in the air. The potential for what this could morph into is exciting.