Hi @ganeshk111
Thanks for reaching out.
I understand that your client wants to have a separate username and password for a 3rd party backend system.
If we click a submit button that 3rd party is calling and send a user data to the another database along with our database via API.
As a first step you can refer to our support documentation: https://woocommerce.github.io/woocommerce-rest-api-docs/#introduction
Kindly be informed that support for customization is beyond the scope of support we are able to provide in this forum. This particular forum is for questions that are related to the WooCommerce core features.
For help with customization we recommend the WooCommerce Developer Resources Portal.
You can also visit the WooCommerce Facebook group or the #developers
channel of the WooCommerce Community Slack. We’re lucky to have a great community of open-source developers for WooCommerce, and many of our developers hang out there, as well.
Lastly, for direct assistance with code customizations, we recommend consulting with the WooCommerce Customizations Partners. https://woocommerce.com/customizations/
Nevertheless, I’m going to leave this thread open for a bit to see if anyone is able to chime in to help you out here.
Cheers