This is what I say the most when I am helping my dad with his tech questions.
Sometimes, I accidentally click on something I didn’t intend to. There is a split second between realizing my error and my reflexes kicking in. This is what can be done (undone).
Hold the click. Meaning don’t let go of the button. Move the cursor away from the button then let go. Now nothing will happen.
Interestingly, if you move it away while holding, then move the cursor back on the button and then let go, it will register as a click.
You are only committed to the click when you let go.