I played through the first level of the game, and I can tell you've put a lot of time into this game. Aesthetically, it's consistent, and the starting cutscene establishes the setting well. (it does have a grammar mistake though)
I liked the particle effects and the pumpkins that can be damaged with weapons.
However, I think that you can improve the game's mechanics and layout.
The opening cutscene should only play once, as it felt boring repeated.
There are no animations or sound when hovering or clicking a button (other than the Unity default), and the scene transitions feel sudden (the BGM could persist through scenes).
In terms of movement, the player keeps moving after a button is released for about half a second unless the opposite movement key is pressed, which made me fall off platforms and into spikes. As others have said, the double jump and wall jump are inconsistent, and combined with the movement issue makes it hard to land on platforms.
There are some oversights in object placement. For example, these spikes don't actually deal damage:
On my computer with a 3000x2000 screen, the title screen sprites were blurred. You should make the source images larger or change the filter mode to prevent this.
More sound effects would be nice, and different BGMs for different environments would really improve the sense of atmosphere.