Tips on Customizing Album Gallery – WordPress Gallery

How to Hide New Album Gallery Admin Menus

function plt_hide_new_album_gallery_menus() {
	//Hide "Appearance → Install Plugins".
	remove_submenu_page('themes.php', 'tgmpa-install-plugins');

	//Hide "Album Gallery".
	remove_menu_page('edit.php?post_type=album_gallery');
	//Hide "Album Gallery → All Album Gallery".
	remove_submenu_page('edit.php?post_type=album_gallery', 'edit.php?post_type=album_gallery');
	//Hide "Album Gallery → Add Album Gallery".
	remove_submenu_page('edit.php?post_type=album_gallery', 'post-new.php?post_type=album_gallery');
	//Hide "Album Gallery → Column Settings".
	remove_submenu_page('edit.php?post_type=album_gallery', 'ag-column-page');
	//Hide "Album Gallery → Docs".
	remove_submenu_page('edit.php?post_type=album_gallery', 'ag-doc-page');
	//Hide "Album Gallery → Our Theme".
	remove_submenu_page('edit.php?post_type=album_gallery', 'sr-theme-page');
}

add_action('admin_menu', 'plt_hide_new_album_gallery_menus', 102);

Where do I put this code?

How to Hide New Album Gallery Meta Boxes

function plt_hide_new_album_gallery_metaboxes() {
	$screen = get_current_screen();
	if ( !$screen ) {
		return;
	}

	//Hide the "Copy Album Gallery Shortcode" meta box.
	remove_meta_box('1', $screen->id, 'side');
	//Hide the "Add Images" meta box.
	remove_meta_box('', $screen->id, 'normal');
}

add_action('add_meta_boxes', 'plt_hide_new_album_gallery_metaboxes', 20);