How to Hide EditorsKit Admin Menus

function plt_hide_block_options_menus() {
	//Hide the "EditorsKit" menu.
	remove_menu_page('editorskit-getting-started');
	//Hide the "EditorsKit → EditorsKit" menu.
	remove_submenu_page('editorskit-getting-started', 'editorskit-getting-started');
	//Hide the "EditorsKit → Styles Manager" menu.
	remove_submenu_page('editorskit-getting-started', 'gutenberghub-styles-manager');
}

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

Where do I put this code?