To join a queue, you need to ask your administrator to add you to the queue. See https://seamlessinsure.atlassian.net/wiki/spaces/SHC/pages/30146768/Phone+Queues#Manage-Queue-Members. You can join multiple and connect to multiple queues at one time. When system routes an incoming call to a specific queue, if you are connected to that queue, you might receive the call based on several criteria: your current status, and your queue’s routing strategy.