This is just a short question. Are both battlers supposed to be taking 0 damage? If not, might there be a common mistake that would be causing this?
Here is a google drive link to my project at this point(Godot 4):
The battlers should take damage here. In the Hit script, in its _init() function, you've inverted the function parameter and the member variable, so the code is not changing the value of the damage member variable. Notice how you assign to the function parameters _damage and _hit_chance instead of assigning to the versions without the leading underscore.