I had this pdf from a few years ago. I had lost the original MSWord document, and I wanted to change it. I went online and Googled a pile of online services. One asked me if I wanted to make my document public. Not trusting them, I moved on. Another accepted my document, and said that I was 5,500 in the queue and it went down by one every couple of minutes. I cancelled that job. I went to another one, and it sent me a conversion into my email box. However it was just an image pasted into an MSWord document, and I couldn't edit it.
I came to the conclusion that I needed my PDF scanned with OCR or Optical Character Recognition. The first one that came up in the search was www.scannedpdftoword.com . Note: This is not pdftoword.com which I didn't like. It had the word "scanned" in the URL.
Bingo. This was it. It promptly sent back an MSWord doc that I could edit. They sell a desktop version as well. I was totally pleased with the result. There was a spelling error or two, but the error was consistent. I would heartily recommend their product and services. I was not paid for this product review, nor did I receive any inducement to make it.
