federated-wordpress-customizations/woocommerce/thank_you_page_customizations.php

<?php

add_action( 'woocommerce_before_thankyou', 'misha_shortcode_or_content' );

function misha_shortcode_or_content( $order_id ) {
	echo '<h3>Please check your email to confirm account creation. Your core is now being provisioned.</h3>';
}