How to Hide Grey Owl thumbnail resize ( Lite ) Admin Menus

function plt_hide_grey_owl_thumbnail_resize_lite_menus() {
	//Hide "Media → Collection".
	remove_submenu_page('upload.php', 'edit-tags.php?taxonomy=collection&post_type=attachment');

	//Hide "Thumbnail resize L".
	remove_menu_page('go-thumbnail-resize-lite');
	//Hide "Thumbnail resize L → Thumbnail resize L".
	remove_submenu_page('go-thumbnail-resize-lite', 'go-thumbnail-resize-lite');
	//Hide "Thumbnail resize L → Settings".
	remove_submenu_page('go-thumbnail-resize-lite', 'gotrl-settings');
}

add_action('admin_menu', 'plt_hide_grey_owl_thumbnail_resize_lite_menus', 11);

Where do I put this code?