Connecting to WiFi network, then rerouting internally

So I'm currently in the road in a camper. Campgrounds typically have wifi. I brought my NAS, Google home, Chromecast, and some other gadgets along that require an internal network.

Is there a way to access the campgrounds wifi and then use that access point to hardwire into a router for a personal network for just our trailer?

I figure I'll probably need something like two routers or an extender and router to achieve this, but my knowledge on weird setups like this is limited.