It's not based on anything in particular, although it is heavily inspired by PbtA/FitD games, especially Blades in the Dark. You can just play it as written, generally following the steps in order. It's probably best played as a journalling game, using the prompts and dice results to guide the fiction as you write, but you can use them however they make sense to you.
I myself had never played or been interested in a solo RPG until I saw Grey Moon Rising a few years ago, so I would recommend that one if you're bouncing off of this one! It also inspired another game of mine with similar vibes.
Let me know if you have any questions about specific mechanics or the process of play, I'll be happy to answer.