Love your artwork! To what people are commenting, I think it's more about refining the mechanics of the movement, player and obstacle hit boxes, maybe increasing the physics for the jumping depending on your momentum. For example, jumping off the vine when you swing - there's no forward momentum, so you sort of just drop down vertically, which doesn't make much sense. Trying to jump off the vine and land on the alligator becomes such an awkward moment.
Sometimes you take damage from the spikes or arrows even when the player model doesn't really touch it, so the hit boxes are likely too large.
I know you're going for a classic/retro game style - but those games were made back then not by choice, but because of the limitations of their programming. I like challenging games, but this style of game doesn't necessarily require skill - just trial and error and lots of repetition, which can get boring when there's no other features/progression in the game.
Checkpoints might not hurt either. It's not really fun to have to redo early levels that you've already beaten countless times. I got to the rock climbing stage so far, but there's similar issues where the hit boxes of things feel awkward and inaccurate. It just felt like too much time wasted to keep trying ha.
EDIT: I beat the game, but the ring puzzle was just by chance with randomly spinning it until it worked.
By the way, do you have any other social media like X or something? Anywhere to message you about a game?