After you connected to remote PC, you can start working as usual. Use your local mouse and keyboard to work on remote PC.
You can copy text on local system, and paste on remote side. Reverse operation is also possible.
If you want to copy files to remote computer, click the File Transfer... button (located on the title bar). Choose "Send File" in menu. Then choose desired files on your PC, and it will be transferred to remote side.
And vice versa, if you need to get some file from remote computer, click the File Transfer... button, and choose "Receive File" in menu. The File open dialog will be displayed on remote desktop, and you have to choose the desired files there.