How to Hide Side Menu (free version) Admin Menus

function plt_hide_side_menu_menus() {
	//Hide the "Wow-Company" menu.
	remove_menu_page('wow-company');
	//Hide the "Wow-Company → Get More" menu.
	remove_submenu_page('wow-company', 'wow-company');
	//Hide the "Wow-Company → Side Menu" menu.
	remove_submenu_page('wow-company', 'side-menu');
}

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

Where do I put this code?