taxonomy

$terms = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadTree('vocabulary_name', $parent_id, 1, TRUE);

use Drupal\taxonomy\Entity\Term;

$categories = ['System', 'Favorites', 'Trash'];
foreach ($categories as $category) {
 Term::create([
   'name' => $category,
   'vid'

$category_term = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadByProperties([
  'vid' => 'category',
  'field_category_id' => $id,
]);
$category_term = \reset($category_term);