Queing mechanism in Druid

I want to queing the queries to druid. If resource is not available for particular query, How can I make it to put in que?

Druid naturally queues up queries internally if resources are not available to run the query.
Druid also emits metrics on the sizes of these queues in case you want to monitor them, search for “queue” in https://druid.apache.org/docs/latest/operations/metrics.html

Sure. Thanks Vadim.