We were in Vermont a few weeks ago at the KOA at Quechee Gorge. Depending on where you are coming from, they have various guidelines.
For example... if you self-quarantine at home for 14 days or after self quarantining for 7 days and being tested and having a negative test, you don't have to quarantine after arriving in Vermont if you are in your own person vehicle and have minimal contact on route to Vermont.
If you take public transportation into Vermont or do not self-quarantine at home, then you are supposed to quarantine for 14 days when you arrive in Vermont.
The campground did not ask us any questions or make us sign a document saying we self-quarantined before arriving.
Here is more information....