What is the best way to copy content from a pdf?

Ideally, get the original Word version, but if this isn't available, Microsoft Word 2013 and later gives you the option to open a pdf in Word and it will convert it: https://support.microsoft.com/en-us/office/edit-a-pdf-b2d1d729-6b79-499a-bcdb-233379c2f63a

If you don't have a recent version of Word, you can try an online converter - there are lots of options if you Google "convert pdf to word".