making custom shortcodes in wordpress code example

Example 1: How to disable Gutenberg / block editor for certain post types

add_filter( 'use_block_editor_for_post_type', 'prefix_disable_gutenberg', 10, 2 );
	function prefix_disable_gutenberg( $current_status, $post_type ) {
		// Use your post type key instead of 'page or post'
		if ( in_array( $post_type, array( 'page', 'post' ) ) ) {
			return false;
		}
		return $current_status;
	}

Example 2: how to add site logo in wordpress

function themename_custom_logo_setup() {
 $defaults = array(
 'height'      => 100,
 'width'       => 400,
 'flex-height' => true,
 'flex-width'  => true,
 'header-text' => array( 'site-title', 'site-description' ),
 );
 add_theme_support( 'custom-logo', $defaults );
}
add_action( 'after_setup_theme', 'themename_custom_logo_setup' );