use NunoMaduro\LaravelConsoleMenu\MenuOption;

...

$menu = $this->menu("Parent menu");

$menu->addOption(1, 'item 1');
$menu->addSubMenu('item 2', function (CliMenuBuilder $sub) {
    $sub->setTitle('Children menu');
    $sub->addMenuItem(
        new MenuOption(
            4,
            'sub-item-1',
            function (CliMenu $menu) {
                $this->result = $menu->getSelectedItem()->getValue();
                $menu->close();
            }
        )
    );
    $sub->addMenuItem(
        new MenuOption(
            5,
            'sub-item-2',
            function (CliMenu $menu) {
                $this->result = $menu->getSelectedItem()->getValue();
                $menu->close();
            }
        )
    );
});
$menu->addOption(3, 'item 3');
$selected = $menu->open();

$this->info("Selected item: $selected");