Macbeth kills young Siward in battle and finds out that Macduff was not born of a woman. A Scottish army is heading towards Birnam Wood to join Malcolm and his English army. Malcolm arrives with the Scottish and English troops at Dunsinane. Macduff kills Macbeth and cuts off his head.
French men were called to duty during the war; thus he became a submariner. Great grandpa and his crew were very lucky; they remained safe. I hope this is right and helpful!