Final answer:
A lighted buoy with a white flashing light showing a group of two flashes in the Irish Sea indicates that you should proceed with caution. It is a general warning and does not specify a course change unless other navigational context is provided.
Step-by-step explanation:
When steaming along the coast of Ireland in the Irish Sea and you sight a lighted buoy with a white flashing light showing a group of two flashes, it typically indicates that you should proceed with caution. White flashing lights on buoys often serve as warnings or alerts, and a group of two flashes could indicate a specific type of navigational aid, like a cardinal mark, which depends on its position relative to a hazard. It does not necessarily mean you should stop immediately, nor does it provide specific instructions to change course to starboard or port without additional context and information about the surrounding waters.