
Here is the quick code snippet of how we can get the current language in Drupal 8 for multilanguage sites.
Get current language code in Drupal 8:
$language = \Drupal::languageManager()->getCurrentLanguage()->getId();
Get current language name in Drupal 8:
$language = \Drupal::languageManager()->getCurrentLanguage()->getName();
Get all enabled languages in Drupal 8:
$languages = \Drupal::languageManager()->getLanguages();