How to Hide the "Simple Website Banner" Admin Menu

function plt_hide_corona_virus_covid_19_banner_menus() {
	//Hide the "Settings → Simple Website Banner" menu.
	remove_submenu_page('options-general.php', 'orchestrated_corona_virus_banner_settings');
}

add_action('admin_menu', 'plt_hide_corona_virus_covid_19_banner_menus', 11);

Where do I put this code?