i am glad you liked the mechanics of the game, about the boot you just need to attach it to the player and when it touches the ground it makes you jump. you can see the screenshots for some guidance. i am sad you didnt discover this because the most enjoyable powerup (the jet) is only accessible after you discover it when jumping with the boot!
i wanted to add an upgrade system to the shield that at some point will show you the location of the enemies but over scooped a bit so had to reduce the content to finish it.
thank you for playing and for the feedback!