Hi Azhar,

Here is the code for that:

jQuery( document ).ready( function( $ ) {
	
	jQuery( '.my-button' ).on( 'click', function( ev ) {
		showLoadingOverlay();
	} );
	
	function showLoadingOverlay() {
		jQuery( 'body' ).append( '<div class="page-loading-overlay"> <div class="loader-2"></div> </div>' );
	}
} );

In this case, just target the elements, I have added .my-button as an example.

I hope it will work fine for you.