After seeing TigerJ's stream this morning I can see I have some fixes to make! For the time being, just know that the controls are:
[F] Fullscreen
[CTRL] Use trinket (shoot the attack button with the gun to hit it from a distance)
[Z,X, or JUMP] Hit the attack button
(Also trinkets equip automatically by just walking up to them)
Thank you so much though for playing my game sorry I kinda forgot to explain things.