Hi Satakshi,
As far as I know OSS Druid cannot do what you are asking, i.e. executing the equivalent of INSERT statements or sending data directly to an API, possibly within an extended transaction.
OSS Druid ingestion methods are Streaming via Kafia/Kinesis, or batch from a variety of sources. Doc ref:
https://druid.apache.org/docs/latest/ingestion/
If you must have a "push" callable API to ingest data into Druid, Imply Polaris is a commercial SaaS version of Druid and has a "Push API" that does what you are asking.