How can I work with IDF file in Open Studio?

edit

You can import the IDF into OpenStudio using the File Menu within the OpenStudio application. The same import option is also available in the SketchUp extension for OpenStudio.

Note that after importing an IDF, OpenStudio will remove HVAC components. You can read posts here and here for more details.

If this is your first time using OpenStudio, I would recommend reviewing the OpenStudio Quick Start Document for a thorough introduction to the SketchUp extension and application.