Separate HTML, CSS, and JS code for given website

I am looking for a freelancer who can help me separate the HTML, CSS, and JS code for a specific website that I have in mind. The primary goal for this project is to update the website design, and I need someone with the ideal skills and experience to help me achieve this.

This is a website:
https://calculator-online.net/uog-gpa-calculator/


If you are interested in working on this project, please let me know your availability and your experience with similar projects. Thank you!
The lowest bid will be accepted.