Stede Bonnet, Gentleman Pirate. The HBO show Our Flag Means Death was a highly fictionalized accounting of his story, but the general outline is right: wealthy landowner gets tired/bored of life with his family and buys a ship to go become a pirate. He is, understandably, terrible at it, and runs into Actual Goddamned Blackbeard, who pretty much just steals his lunch money then and there, but after a time decides to help a brother out and actually teaches Stede to be a not completely shit pirate. Neither one lasts much longer before getting caught and executed, but what a bizarre and hilarious journey.

https://www.smithsonianmag.com/history/the-gentleman-pirate-159418520/