How can you make a flickering object that won't overlap other UI elements?

Question

Unity

Let's say there is a clicker, I want a full-screen panel to appear when the button is pressed and to make it flicker in different colors, but I don't know how to make it flicker (I heard that it's possible through IEnumerator, but xs how) and I have no idea how to do it at all its transparent in terms of click, so that there is only an image

Answer 1

and generally no idea how to make it transparent in terms of click

Well, if it's on the canvas, place a Group in the canvas and turn off its interactivity. Well, or remove the raycast target