USB 2.0 is supposed to work with cables up to 16 ft. The longest I've used was about 8 ft. But as long as the computer recognizes the USB wifi adapter plugged in, it should work.
No but you could buy a long USB cord and a wifi adapter. Longer cords (usually around the 10 foot mark) require an active repeater and could add some latency but nothing to horrible beyond that.
i ask because cases seem to be adding usb ports on the right side and i need one of the left but i cant seem to find one like this so i have to resort to getting a usb wifi adapter extenter