Would suggest you go to the Mobile Internet Resource Center (on line). The free section is sufficient to attain a basic understanding of what is available. All sorts of options are available.
I am a full timer that works from my RV. I tried cell phone boosters and was disappointed.
When we were in the process of selling our house, we stayed at the Charlotte Motor Speedway camping grounds for a month or two. The campground WiFi was horrible with very few people there. I can't imagine what it would be like during an event.
I eventually went with a cellular modem/router from Peplink. The device I use is favored by first responders, the transportation industry, is used by boaters & many on this forum. I have been very pleased with it over the last two years.
I am in the process of evaluating a Starlink satellite setup for inclusion in the LAN on my RV. When everything is complete; I will have the ability to receive internet signals via WiFi (park provided), cellular, Starlink satellite & cable (doubt availability if ever).
I assume you bus conversion will be in a metal shell. You will most likely need an external antennae. If internet connectivity is important to you, be prepared to invest a few dollars in equipment & service.
Good luck & safe travels.