There are many tools and a lot of software out there to convert PDFs to Word.
Online tools like:
convertio.co
altoconvertpdftoword.com
For Ubuntu we have tools like LibreOffice, abiword, and pdftohtml. In most cases the best results are found when using a combination of tools. I either use then online tool luminpdf in combination with LibreOffice Draw. And if I want I can copy paste and merge into a Libre Office Writer document. It really depends on the situation. You might also want to try the pdf import extension for OpenOffice: https://extensions.openoffice.org/en/project/pdf-import-apache-openoffi…
lowriter --headless --convert-to docx test.pdf
abiword --to=doc test.pdf
pdftohtml -noframes -q -p -c "test.pdf" "test.pdf-img.html" -> then open the html with LibreOffice Writer and save it in desired format.