Firstly, download and install the suitable USB drivers for your device, you can download Samsung KIES for verifying if the suitable drivers are installed on your PC.
Secondly, download the Official Jelly Bean 4.1.2 XXLT6 Firmware file and save it in your PC.
Now, download Odin app and save it in your computer, after the download is done extract the ODIN archive on your desktop folder PC and install the ODIN app.
Extract the downloaded update file on your PC.
Open Odin.
Power off your Note N7000 device.
Boot it into Download Mode, for entering into Download Mode for Galaxy Note N7000 device, you have to press and keep holding the Power + Volume Down + Home buttons on the same time.
Now, with your device booted into Download Mode, connect...