Poi(s)son is a wonderfully inventive game! The core mechanic is genuinely clever, and the tension between speed and precision is palpable.
To take it to the next level, a few tweaks focusing on clarity will make a significant difference.
The current font is hindering the typing section more than it should, so swapping it out for something more legible is a quick win. While maintaining the aesthetic, ensure the W, H, N and O, Q, D are very distinct.
Likewise, the fish cleaning section needs a bit more guidance to get players oriented; a few visual cues or a quick tutorial would work wonders. For example, you could add a dotted line indicating the precise cutting point, accompanied by a scissor icon that animates upon a correct click.
And, of course, immediate feedback will help players learn and master the mechanic. Think of adding a playthrough video on the itch page as a helpful reference point for players.
You still got few hours left, I highly recommend you to have a little refinement!