I had this system for a while
https://www.ccrane.com/item/ant_wifi_vect_homer/102/cc_vector_home_wifi_repeater_system_orphan but discovered that most campground and other wifi systems I wanted to use were so poorly designed that throughput was almost worthless.
We now have an unlimited data account with our cell phone provider and I have a Mifi that gives me fast LTE speed access for all our devices (will handle up to 16 devices). It costs more per month than a limited cell account but I have found that we get better throughput and pretty good coverage across the US and Canada. There are times when I can't get an LTE signal but in those locations I usually couldn't piggy back on someone's wifi either.