Working on a challenging project, need suggestions

Yesterday, I suddently decided to simulate and Undertale fight.
For now I just did the arena and menu selection and now I am planning to create the events on the selection of a button, before starting with the hard part (the fight).
Here’s my project.
I would like to know if I can do something better from what I have done now, and have some suggestions about how to proceed or something like this, idk.
Thanks in advance