Get the data of any user by ID.
fusion_get_user( int $user_id [, string $key ] ) : mixed
$user_id (int) (Required) User ID.
$key (string) (Optional) The key of one column. Default value: null
(array|string) Associative array of all data or one column by key.
$userdata = fusion_get_user(1);
echo $userdata['user_name'];
// admin