there appears to be a bug in your game, as soon as i release spacebar the player teleport to the start.
Edit: I figured it out, the jump with W key is working fine.
Viewing post in Mirror Of Hope jam comments
Hello,
This does not appear to be a bug. The issue is likely related to your frame rate settings. Please make sure your FPS is set to 60 or 90, as the game mechanics depend on a stable frame rate. Once adjusted, you should be able to play normally without the player resetting position.
Thank you for your understanding.