$cache_metadata = new CacheableMetadata();
$cache_metadata->addCacheContexts(['url.path']);
$cache_metadata->addCacheTags(['node:123', 'node:512']);
$cache_metadata->setCacheMaxAge(0);
$build = [
'#theme' => 'theme_name',
'#var_1' => '',
'#var_2' => '',
];
$cache_metadata->applyTo($build);
$renderer = \Drupal::service('renderer');
$html = $renderer->renderRoot($build);