WooCommerce – external PHP page that sets the cart checkout details

Hi All

I have a registration form that users must fill out first to register with us for a service it then adds a product to the checkout.

I have all the details for the customer and for ease of use i don’t want them to fill the information again, so for a better user experience i wanted to populate the fields automatically as I already have them and it seems like a no grainer!

Any help would be greatly appreciated,

Regards