Good question! Unfortunately, it’s one with a very dissatisfying answer - we do not know with any certainty in most cases, and have little way of finding out from a distance of three centuries. As Colin Woodward points out in his very enjoyable The Republic of Pirates, there is a severe paucity of any primary source material about Golden Age pirates. This has meant that it’s an area that has not received a great deal of scholarly attention until the last few decades.

Often there is enough reliable primary source material to draw conclusions about these men (and some women!) during the course of their careers, but 18th century historians were unfortunately not interested in recording the details of their pre-piratical lives. In some cases, that is not so - for instance, we know about the origins of Sam Bellamy and Stede Bonnet in some detail, but they are outliers. The primary source of contemporary biography on Golden Age pirates is A General History of the Robberies and Murders of the most notorious Pyrates, published in 1724 by the pseudonymous “Captain Charles Johnson,” is of very questionable value. While it purports to give true accounts of the lives of various pirates, its unclear authorship and fantastical portrayal of the lives of its subjects (largely unsupported by other contemporaneous sources) means that anything in it comes with a major asterisk. It’s a great read for anyone interested in the development of the myth of pirates today, but sadly, the information you’re looking for is lost to history in large part.