save-level-and-checkout-date-to-user-meta.php

<?php
/**
 * Save the user's membership level name and the order date as comma separated values to the user meta.
 *
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */
function my_pmpro_save_level_and_checkout_date_to_user_meta( $user_id, $morder ) {

	$user  = get_userdata( $user_id ); // user object
	$level = pmpro_getLevel( $morder->membership_id ); // membership level object

	// Exammple: Save the user's membership level name and the order date as comma separated values to the user meta§
	$membership_level_name = $level->name;
	$order_date            = date( 'Y-m-d H:i:s', current_time( 'timestamp' ) );
	$meta_key              = 'membership_level_and_order_date';
	$meta_value            = $membership_level_name . ',' . $order_date;
	update_user_meta( $user_id, $meta_key, $meta_value );

}
add_action( 'pmpro_after_checkout', 'my_pmpro_save_level_and_checkout_date_to_user_meta', 10, 2 );