ok,
" set it with my computer through the usb cable"
is not the same as
"One ardiuno with a USB touch pad and sending data "
So what's it going to be? Arduino would need a USB Host shield to control a USB touch pad.
Controlling a simple matrix keypad on the other hand is easy.
16, 20 button keypads are also available.
The wireless interface is more straightforward, be it wifi or some other kind of RF.