Hi rgos.assoc1,
Thanks for reaching to us and take our apologies for the long delay in answering due to the weekend.
You can use WoodMart WooCommerce builder, which allowing you to create custom Checkout page. You can find the Layouts under the Dashboard > Layouts.
Further, you can read more about the Layout Builder here:
https://xtemos.com/docs-topic/woodmart-woocommerce-layout-builder/
Please note that we do not give a guarantee for full theme compatibility with all existing 3rd party plugins. Sometimes, not always, you need additionally customize the theme or plugin to make them work together. Unfortunately, it’s not possible for the author to make the theme compatible with all the existing plugins and additional customization is outside the scope of our basic support.
Regarding Billing details, it is default WooCommerce functionality and WoodMart does not control it. You need to find a third party plugin to achieve more functionality that best suits you or I kindly suggest that you reach out directly to the WooCommerce support team, who are better equipped to provide you with the guidance you require.
Regards,