How to create a website using the quote tool of another website?

Hi, I have no idea what I am doing! I’ve created a website previously using wordpress and that’s about as far as my website development is capable of.
Anyway, I would like to create a simple website (a couple of pages) where the customer enters their details for their car (reg, and postcode) and a quote is calculated to show them how much their car is worth. I would like the quote to be calculated from a different website, but anonymous and the customer stays on my website. And it would take off a certain percentage. Is there any technology which would enable me to add this onto my website without having to write a lot of code? Please let me know if you have any questions. Thanks