Hi
I was wondering if It’s possible to make an script in which you can, in the editor, select a list of functions who will be called when a certain function in the script will be invoked, just like the onClick box in a button script: 
Thank you for the help.
The OnClick function for a button contains a class called UnityEvent. If you have a public UnityEvent on your script, it will show exactly the same GUI in the inspector as the OnClick box.
You call the UnityEvent by calling it’s Invoke method, which will make every function you’ve added in the inspector be called.