If you said that space was a control, the game would have been more easy, i only found that you needed to press space to continue moving by luck. Also the music plays itselfs several times at the same time sometimes. At the beginning of the wave, it lags on my computer (probably Gdevelops pathfinding, not your fault). But the core gameplay is fine, and that's what matters in a game ! Also this is your first game, so don't worry all those problems.