The first funeral is for the King of the Danes, in lines 1-52. This funeral serves as a way to introduce the setting and the storyline.
The second funeral is for Hildeberg's family in lines 1007-24. They were killed during Beowulf's battle with Grendel.
The last funeral they probably want you to mention is Beowulf's funeral in lines 3137-82. Beowulf is cremated and buried with all the hoard of the dragon he died killing.
Some commentators have made the argument that there is really a fourth funeral, that of "The Lay of the Last Survivor" found in lines 2247-66. Although this is never explicitly called a funeral, many references are made to rituals that are normally only performed at a funeral.