Build me a macronutrient and calorie calculator for my website, embed it in my website and connect to a pre-designed Word document/output downloadable PDF for client

Build me a macronutrient and calorie calculator for my website, embed it in my Wix website as a webpage and connect to a pre-designed Word document/output downloadable PDF that my clients can access on my website and download. I have the copy pre-written, I just need a script to be made to automate this functionality and it to be embedded and tested as working within my website.

Example for reference - https://aestheticstrength.co.uk/calculator/