I am new to the android studio

I have importing PhoneGap project into the android studio.

Here I am getting this error

This project does not use the Gradle build system. We recommend that you migrate to using the Gradle build system.

and I don't know how to use android studio

I did following steps.

1. node.js and PhoneGap and android studio installation
2. PhoneGap project creation
3. add the Android platform to PhoneGap project and build android
4. import the project into the studio (I have imported whole app not only android platform)

after this, I'm getting

Migrate Project to Gradle?
            This project does not use the Gradle build system. We recommend that you migrate to using the Gradle build system.
            More Information about migrating to Gradle
            Don't show this message again.

How can I solve this? and how to run the project? and how to proceed further in android studio+Phonegap project