There are no dumb questions...That's how you learn and stay out of (costly) trouble...Driving on a PUBLIC road to public is fine.
Example...If you come upon a gate that's open and a 100 yds away is public land and you're on that road...It is NOT legal to cross that land to get to the public, it's private (it will no doubt have plenty of no trespass signs)...If that same road is a legal access road to that public property, it is legal...Must be legal access road and many times will state this.
Example...If you come upon a gate that's open and a 100 yds away is public land and you're on that road...It is NOT legal to cross that land to get to the public, it's private (it will no doubt have plenty of no trespass signs)...If that same road is a legal access road to that public property, it is legal...Must be legal access road and many times will state this.