Yes. Menus are confirmed a few weeks before travel, and each journey page then shows a View confirmed menu link. Until then you can browse sample menus for day trips, lunches and Christmas journeys. On the day, you choose your dishes from the confirmed menu.
If something on the menu doesn't suit you, let us know your dietary requirements at least 14 days before you travel. You can add them yourself in Manage booking before your tickets are issued.