Cute and fun game, I like the drawings and storytelling. The multiple paths you can slither across was designed well. The controls are bit wonky, perhaps it needs to be more responsive by applying a sharp impulsive force to the rigidbody when moving against the acceleration (useful for making sharp turns) - after all, you’re supposed to be a snake, not a ball. Gravity should also be increased a bit, it’s a little too floaty. Some of the tubes are really narrow so it’s very easy to fall off; I suggest having checkpoints when things get difficult. The birds’ hitbox needed some adjustment, it sometimes didn’t feel right getting hit at the empty spot in front of the bird.
Bonus points for making the quit control be actually moving the snake into the exit hole - I had this idea for my game too but didn’t have the time to implement it. Overall, it’s pretty creative. Great job!