In order to queue for an Island Expedition scenario, you have to go to the Port of Zandalar (Horde) or to the Boralus Harbor (Alliance). There is a table that opens the queue window where you select the type of Island Expedition you wish to queue for: Normal, Heroic, or Mythic. Or whether you will queue alone or as a team.
You get access to Island Expeditions at level 116. The quest to start your first Island Expedition can be found at Port of Zandalar or Boralus Harbor.
|1. Quest: Island Expedition (Alliance) -- Part 2|
|2. Quest: Island Expedition (Horde)|