How to adding form fields to a page

Hi, I am a newbee to WordPress. I need to create an order form page. I have an order form page that was created by someone else (it uses Java Script and PHP) that I would like to use if possible.

I do not know how to incorporate it into WordPress.

If I can not use The form I have, I need to know how to create a form page to work with wordpress. I would be happy to share the code.

Thank you for your help.