How to install Realtek 818b driver in black board manually

Hi!
I just started up my new beagle bone black board and I need to connect it to Internet. I have a Realtel 818b external device to be connected at the USB connector.
However, I need a bit of help.
The board recognize the device, but the connection is not established.
I understand that I need to download the driver in the Drivers folder and install it manually.
Please, could you help me?

Thank you!