I want to implement a function where I want to display the data in the dialogflow chatbot that is retrieved from BigQuery using a select statement.Is this possible.Kindly help
Based on what was mentioned in the comments sections, seemingly Dialogflow Fulfillment is exactly what you need here. When user types an expression, Dialogflow matches the intent and send webhook request based on the adjusted fulfillment function, the webhook service then performs the intended action like calling API services or affording some other business logic processes.
Dialogflow integration with Bigquery also requires applying fulfillment code to compose appropriate GCP Cloud function that will handle communication with Bigquery API service. Said this, you can use built-in Inline editor and write your fulfillment function, however it doesn't accept any other then Node.js programming language.
Saying more about implementation, I think you can follow codelabs tutorial which provides in detail the general workflow, assuming that you can inject your own code replacing the domestic addToBigQuery() function in Index.js from the example. For this purpose you can visit nodejs-bigquery Github repository containing a lot of useful code samples, in particular the generic query() function that might match your initial aim.