An interesting idea. Had some jank and the platforming controls can be refined, eg it falls quite slowly, and gets caught on walls. I'd also recommend incorporating coyote time and jump buffering, which are useful platformer quality of life mechanics.
Besides this, the puzzles were pretty good. As far as the theme goes, you have to die to change your movement options, which mostly amounts to killing yourself once per level, which I'd say is an alright gimmick but doesn't have much room for development, eg, the gimmick could have been you choose your abilities when you spawn and the levels would have played the same. It might have been better if the puzzles needed changing of abilities, which I think is what the checkpoints were for? But I didn't change my movement abilities at all after the first death.
Finally, I think the dev put the resolution to something strange, which caused some bugs with UI being offscreen and alt-tabbing crashed the game. This is an unusual choice probably made for the pixel art, but seemed to only cause the above bugs.
Overall, very solid entry, especially for a first jam. Novel concept, could do with some more interesting puzzles and refining the main mechanic and the player controller. Good work!