If you can get a wifi signal outside the camper and not inside, you can mount a wifi extender inside the window to rebroadcast the signal inside the camper.  Wifi has a difficult time going through the metal on the outside of the camper.

Here is an inexpensive extender that I have successfully used in the past.

https://www.amazon.com/dp/B07N1WW638/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B07N1WW638p13NParams&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExUFM5TUMwNFlaNEo4JmVuY3J5cHRlZElkPUEwMTk1MDgxMTdKSzNMMFJMSkEyMiZlbmNyeXB0ZWRBZElkPUExMDQwODY4M0hNTU84SkVHQlRHSSZ3aWRnZXROYW1lPXNwX2RldGFpbDImYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl