Image marking/drawing in form

Hi all, I'm trying to bring paper forms into the digital age by converting some paperwork we use to an online form.

There is one form where there is an image (the same image), an outline of the human body. The user is supposed to mark where there is a concern. Usually this is done with pencil/pen, but now I would need to have the person 'draw' on the image and save it.

I was using google forms for all the forms, but that might not work here. I have formidable wordpress forms (free version) but I can't think of a way to use the html function for this.

I know my way around technology, but I'm not a developer by any means whatsoever. Any ideas?