Hello,
Yes, WoodMart provides options to customize the checkout fields and checkout layout.
If you are using the classic WooCommerce checkout with the [woocommerce_checkout] shortcode, please go to:
Theme Settings > Shop > Checkout
Enable Checkout Fields Manager and then navigate to:
Dashboard > WooCommerce > Checkout Fields
From there, you can manage the Billing details and Shipping details fields. You can reorder the fields, change their width/position, make them required or optional, and show/hide fields.
If you want to customize the overall checkout structure, you can also use:
Dashboard > Layouts > Checkout. With Elementor/WPBakery, you can create a Checkout form layout and add the Billing Details, Shipping Details, Order Review, and Payment Methods elements as required.
https://xtemos.com/docs-topic/checkout-page-builder/
Regarding making fields greyed out/non-editable, this is not an option provided by the Checkout Fields Manager. It controls the visibility, order and required/optional status of the fields, but it does not make checkout fields read-only.
Best Regards