retrieve WordPress user info

<?php
/* visit us - https://wpgenie.org */

/* Retrieve WordPress user info */

$user_info = get_userdata($user_id);

$username = $user_info->user_login;
$first_name = $user_info->first_name;
$last_name = $user_info->last_name;

echo "$first_name $last_name logs into her WordPress site with the user name of $username.";