If you own a car, car camping around the state lands and national parks would totally be doable.
I did a 2 month road trip. Fuel is cheaper in US than muxh of the world. Groceries too. Restaurant food has gone way up with inflation.
Problem is you can't really buy a car as a foreigner. And renting one for 3 months is going to be insane.
Van, campers rentals were expensive when I looked in 2019. Cheaper to stay in a hotel. I can only imagine now after the COVID hype how expensive they are.
Hostels aren't really a thing in the US, so finding a place to sleep for under $50 a night is a challenge
Cuba at nearly $5k seems inaccurate.
Offical exchange rate is 24:1 USD. But real life was 80 last time I heard. This may be the problem.