Congratulations on making your first game! I think other people with better knowledge of platformers game design have already covered how to make the controls feel better, but I had a few other pieces of feedback:
1) I think for future games, you might want to consider making the instructions just be in their own box instead of in the world, since with this setup, often I couldn't actually read them fully until I was far enough along that they weren't particularly helpful anymore.
2) I suspect you're using an AZERTY keyboard to develop? That threw me for a loop, because I'm used to game instructions assuming you have a QWERTY keyboard, so usually the controls are labeled as WASD.
I hope you keep making more games after this jam!