I can't figure out what's wrong in my code

[user85]

Godot Version

4.4.1v

Question

My vision

the reality

I can’t even tell where the error in the code is.

[ananasblau]

You didn’t post any code or the screen tree so that makes finding errors in your project a bit hard. But for the UI being messed up, I suspect something about your UI layout is wrong. If you anchor parts of your UI differently, say some from the top left, others from the center, then it can look broken in the game, especially on different sizes.
Read about anchoring UI elements and the use of containers, I’m sure you can fix your problem.