can someone help me change function to run codeigniter 4 ?

Glad that you figured that out, but that's how i would write it

PHP Code:

public function vlDemos(int $parent_id = 429){
  return $this->db->table('categories')
              ->select('id, name')
              ->where('parent_id', $parent_id)
              ->get()
              ->getResult();
}