How to Hide Billflow Admin Menus

function plt_hide_servicebot_menus() {
	//Hide "Billflow".
	remove_menu_page('servicebot');
	//Hide "Billflow → Billflow".
	remove_submenu_page('servicebot', 'servicebot');
	//Hide "Billflow → Stripe Webhooks".
	remove_submenu_page('servicebot', 'servicebot-stripe-webhooks');
	//Hide "Billflow → Setup Roles".
	remove_submenu_page('servicebot', 'servicebot-setup-roles');
}

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

Where do I put this code?