How to extract data using dataextraction in Adobe Campaign ? and how to write a query that will update or insert values to schema with the values fetched from another schema?

Here is a documentation link on using the Data extraction (file) activity:

Action activities

When extracting a file to use for an external delivery, you should always use a Delivery activity with an External routing.

To move data from one table to another, create a workflow with a Query followed by an Update data activity. You can find out more about this in the Administration training course.