Enqueue Styles & Scripts in GP

/* Enqueue styles to editor iframe */
add_filter( 'generate_editor_styles', 'rbd_editor_iframe_styles', 50);
function rbd_editor_iframe_styles($editor_styles ) {
    $editor_styles[] = '/style.css';

    return $editor_styles;
};

/* Enqueue Customiser CSS to editor iframe */
add_filter( 'block_editor_settings_all', 'rbd_customiser_styles', 10, 2);
function rbd_customiser_styles($editor_settings, $editor_context) {
    $custom_css_post = wp_get_custom_css_post();
    if ($custom_css_post) {
        $customiser_css = $custom_css_post->post_content;
	    $editor_settings['styles'][] = array( 'css' => $customiser_css );
	}
    return $editor_settings;
};

/* Enqueue custom script to editor */
add_action( 'enqueue_block_editor_assets', 'rbd_enqueue_block_editor_assets' );
function rbd_enqueue_block_editor_assets() {
    $theme_dir = get_stylesheet_directory_uri();

	wp_register_style( 'rbd-editor-styles', $theme_dir . '/editor/editor-style.css' );
	wp_enqueue_style( 'rbd-editor-styles' );

    // Editor script
    wp_enqueue_script(
        'rbd-editor-script',
        $theme_dir . '/editor/editor-script.js',
        array( 'wp-hooks' ),
        time(),
        true
    );
}

/* Frontend custom styles */
add_action('wp_enqueue_scripts', 'rbd_enqueue_custom_styles', 20);
function rbd_enqueue_custom_styles(){
	wp_register_style( 'rbd-child-custom', get_stylesheet_directory_uri(). '/custom/custom-style.css' );
	wp_enqueue_style( 'rbd-child-custom' );
}