How to Hide Form Maker Admin Menus

function plt_hide_form_maker_menus() {
	//Hide "Form Maker".
	remove_menu_page('manage_fm');
	//Hide "Form Maker → Forms".
	remove_submenu_page('manage_fm', 'manage_fm');
	//Hide "Form Maker → Speed Optimization".
	remove_submenu_page('manage_fm', 'twb_form-maker');
	//Hide "Form Maker → Submissions".
	remove_submenu_page('manage_fm', 'submissions_fm');
	//Hide "Form Maker → Themes".
	remove_submenu_page('manage_fm', 'themes_fm');
	//Hide "Form Maker → Options".
	remove_submenu_page('manage_fm', 'options_fm');
	//Hide "Form Maker → Ask a question".
	remove_submenu_page('manage_fm', 'https://wordpress.org/support/plugin/form-maker/#new-post');
}

add_action('admin_menu', 'plt_hide_form_maker_menus', 11);
Where do I put this code?