"The princess was finally found" -- whew! It's like you knew how many tries it took me and added that "finally" in advance :). Nice job on this and congratulations on your first game -- you had several levels here with many different types of platforms and different mechanics, which is great. The grappling-hook mechanic seems like it's notoriously difficult to get to work right in games, but in the portions of platforming that were designed for it in this game, I thought it worked well. I also enjoyed the platform that carries you a distance and then ejects you -- those are just fun to ride. And perhaps most of all, I liked that this game had an otherworldly strangeness to it, in the abstract backgrounds that are often just barely indecipherable, and in the coloring. Nice!
I'd echo the point made elsewhere that the script on your camera should track the player in such a way that there is always some distance between the player's feet and the bottom of the screen (and head and the top of the screen), particularly in a game like this where you are descending downward. I got some feedback on an early game of mine that there should never be any blind jumping at something you can't see below, and I've avoided that ever since. (As an alternative, you might have the camera fixed vertically, but colliders that you touch that shift the camera down one full level, and then remains vertically fixed again). I'd also look into "coyote time" and how to add that to your character controller, for a nice feel on all these close jumps. Finally, I'd suggest either giving your character a full double-jump (with the jump force about the same on the first and second jump, and limited to only two jumps), or none at all -- here, one could rapidly press jump to have the character descend indefinitely up into the air, and with small/uneven amounts of upward force. Sometimes I'd do it and hit my head on a collider that was probably intended for falls from the level above, and I'd be killed. As you've probably heard before, if you have the luxury of a non-participant who can playtest while you watch, that always unearths issues one is often blind to in development. I hope that's all helpful feedback -- nice job again on this!