You can use Groovy scripts to copy files in your file system.
Where to use
You can use this script anywhere in ReadyAPI.
Example
Groovy
//Import libraries for working with files
import java.nio.file.Path
import java.nio.file.Paths
import java.nio.file.Files
//Create objects for the copied file and the target file
Path source = Paths.get("C:\\Users\\elle.stevenson\\Desktop\\test.xlsx")
Path target = Paths.get("C:\\Users\\elle.stevenson\\Desktop\\out\\copied.xlsx")
//Copy the file
Files.copy(source, target)