This is rad for a first game! The rock following you in the final part was super cool! I'd love to see that expanded. I also love the simple cinematic you made, that added a big touch to the style. There definitely needs to be a larger distinction between intractable / damaging objects and background elements though. The first brown vines(?) at the start I instantly died to out of confusion. That brown mixes with the brown ground. Similarly, the floating platforms were dark green on a dark green background.
I recommend looking into basic color theory. Nothing crazy, but contrast is important (If the background is dark, the intractable obstacles should be bright. If the background color is a cold color, the platforms should be a warm color). Otherwise though this is awesome! Great job starting your game making journey.