The USB port on the tv is probably not for wifi input. Usually The USB port on a TV is designed to handle a media device, e.g. a memory module or maybe a disk drive with a USB cable attached. That enables you to display photos or play movies stored on a USB stick, for example. Smart TVs use either wifi or or direct LAN cable connections. A typical Wifi antenna with a USB plug on it probably will not function in the tv USB port becasue there is no device driver in the tv to operate it via the USB port. Check your tv manual concerning what can be plugged to its USB port.
If you want to boost park wifi to assist your tv, you need a wifi booster gadget that re-broadcasts the wifi. Maybe something like this:
http://www.bestbuy.com/site/d-link-n300-wi-fi-range-extender/5052300.p
The tv's own wifi receiver will pick up the signal.
I doubt if any of this will make tv streaming any better in most RV parks, though. Typically they lack an internet connection that can provide the data rate that video demands. It may work ok in off-peak hours, but other users in the park will interfere during prime time.