Edit the checkout billing details Form

Hi, I would like to edit the HTML on the checkout billing details Form that is on the checkout page for the RFQ submission form. I just want to change a few of the field titles and take away the second astrick on the required fields. Nothing major but can’t find the form HTML. I see the php file for the form but does not contain the field titles.

Thanks

https://www.ads-software.com/plugins/woo-rfq-for-woocommerce/