<?php
$host='localhost';
$db='-';
$user='-';
$pass='-';
$charset='utf8mb4';

$dsn = "mysql:host=$host;dbname=$db;charset=$charset";
$opt = [
PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES   => false,
];

try
{
     $pdo = new PDO($dsn,$user,$pass, $opt);
}
catch(PDOException $e)
{
     echo $e->getMessage();
}

class user {
    public function register($prenume, $nume, $mail, $parola)
    {
        echo('Accessed user class');
       try
       {

           $stmt = $pdo->prepare("INSERT INTO utilizatori(prenume, nume, email, parola) VALUES(:prenume, :nume, :email, :parola)");
           $stmt->bindparam(":prenume", $prenume);
           $stmt->bindparam(":nume", $nume);
           $stmt->bindparam(":email", $email);
           $stmt->bindparam(":parola", $parola);
           $stmt->execute();
           return $stmt;
       }
       catch(PDOException $e)
       {
           echo $e->getMessage();
       }
    }
}

$user = new User();
$user->register('prenume','nume','email','parola');