[HELP] How would I tackle creating my system?

Greetings! I've recently completed my game and want to create a sheet for it on Roll20. I'm unfortunately not proficient at code. I created the rule system for my game as a form fillable PDF. I'm unsure if that will help me get started quicker. A page example <a href="https://i.imgur.com/QWcTSQ3.png" rel="nofollow">https://i.imgur.com/QWcTSQ3.png</a> Is there a way in which I can add the pages of the PDF as images, and then simply overlay text where the light blue fields are? Perhaps some form of PDF integration? I guess what i'm looking for is "What would be the best starting point with the things I have?" I appreciate the time and advice you have to offer.

The sheets are made in html/css, so using that pdf as basis to create a sheet would be hard, but not impossible. I converted a .doc to html fir one sheet I created, and the code was horrible to edit with all it's redundant divs, classes and auto-generated naming-convention. It would be better to start from the code of a similar-looking sheet, and work from there. There are guides in the wiki for creating sheets and tips, and html/css help can be found on the web.