how can i save a video from project folder (ASSETS) to android internal or external storage?

how can i save this videos using the application to android storage? thanks in advance.

Put the videos in either Assets/Resources or Assets/StreamingAssets. Use the WWW class to grab the data, and then save it to the persistent data path.

This example saves an xml instead of a video, but what you do will probably be similar.

using (WWW retriever = new WWW(Application.streamingAssetsPath + "/Example.xml"))
      string pathToStorage = Application.persistentDataPath + "/Example.xml";
      System.IO.File.WriteAllBytes(path, retriever.bytes);              

Also, make sure you add the proper permissions in the AndroidManifest.