You will need to have a big enough data plan to do this over the internet. Some folks use their cell phone for this but this ties up your cell phone.
I would get a separate system like the Verizon MIFI or one of the other several units like this available. Having 4G capability would be best solution but of course 4G is not available everywhere. We use the Verizon 2200 Mifi unit for our internet use all over the east part of the US and serves us well getting on the internet.
I am not a fan of tapping into the open WIFI connections you find everywhere. Always afraid it will bite me in the end.
The local camp grounds frown on high usage of their WIFI connections for down streaming things. This takes away the WIFI from the others camp ground users big time...
We use the OTA Batwing antenna to pull in the local town high def Natl Broadcast HDTV signals for all of our HDTV watching. This is free to use and we pick up 6-36 full blown wide screen HDTV Signals just about anywhere we go here on the East side of the US. Much better to watch full blown HDTV verses the cable TV channels offered by the camp grounds. Of course this is only the National TV networks so when we want to watch cable channel stations we will use the camp ground connection or downstream from the internet.
If movies is all you want to watch then pick up a elcheapo DVD player from WALMART for $20 and hookup to your bedroom TV and bring along movies with you to watch... We do that as well... Always got to have a PLAN B when camping...
Roy Ken