How is a program designed?

Question

User interface

Hello. I'll ask a stupid question, but please answer Everyone started somewhere.
I have basic knowledge in Java for example. I understand how complex programs are written. Explain how all these buttons are made, the design of the program, and most importantly, how it connects to the code?
I'm still far from it, but it's interesting.
Thank you.

Answer 1

Something like this: a button is dragged onto the form;
for each button, you can add an event, for example, pressed, let down, released, etc. where it says what we want to do