是否需要准备好的语句来获取值

Question

是否需要准备好的语句才能获取值？如果是这样，我找不到参考。我正在使用预准备语句写入MYSQL。这是我的工作代码。感谢

//Check that Email matches Password, then get First Name and start session
if ($getFname = mysqli_fetch_assoc(mysqli_query($con, "SELECT userFname FROM users   WHERE userEmail = '$userEmail' and userPassword = '$userPassword'"))) {

    //Grab first name
    $data = $getFname['userFname'];

    //assign unique session ID
    $_SESSION[Email]=$userEmail;

    //Remember first name
    $_SESSION[Fname] = $data;

    //go to dashboard page
    header ("location: dashboard.php");}

}else{ 
      $error2="Email and Password do not match, please try again."; 
    }