Or if you have a real C64 with a CRT that would be best, but than with some kind of mass storage attached (anything that is faster than a 1541 since the game is so big it has to load before every fight or other activity).
The game can be pretty immersive and playing it through is a multiple hour endeavour.
If in a ship to ship fight, you gotta raise sails first (by moving the joystick up).
Edit: Vice is an emulator packaged in Debian Contrib, but you need the C64 ROM file (easy to find online).
https://archive.org/details/msdos_Sid_Meiers_Pirates_1987
https://archive.org/details/PiratesMacintosh
There are probably others, but Archive.org is misbehaving at the moment.
tbh if you want to scratch the pirate-y itch, Assassin's Creed Black Flag is excellent, if just for the sea shanties.
Which has itself just had a remake released for it I see! I don't keep up with games these days.