I'm not gonna lie, I do not know what HTML5 is but do you have a way to play it in browser or something available on chromebook?
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Hi Eli, I've uploaded the demo to opera gx.games https://gx.games/games/wdcf5d/back-to-the-dark/ which will run in a browser, but the browser needs to be opera, although your chromebook should be ok for that. I think.
Although if you install opera you might want to be careful about setting it as the default browser. They tend to do that.