<?php
$user_id = 1;
$key = 'my-field';
$single = true;
$user_last = get_user_meta( $user_id, $key, true );
echo $user_last;
?>
<?php
$user_email = 'pochta@mail.ru';
$key = 'customname';
$single = true;
$user_last = get_user_meta( $user_email, $key );
echo $user_last;
?>