I haven't done the full length of one but I've gone pretty far down one before
Basically you just need to figure out who owns the land and depending on that would depend on if you can legally or not
When I did it though I didn't check first because I was basically banking on the fact it was near a national forest so if someone stopped me I'd claim (accurately) that I didn't know it wasn't a part of the national forest. Of course I'm not sure if it is a part of it or not, but if I did get stopped at least I'd know for sure. I didn't get stopped but I did have a nice day out there.
Because it's not needed outside the eastern US. The vast majority of land around me is public and anyone can go out. Right to roam would just give me the right to trample through someone's property when there's plenty of public land to go around it with, which is what right to roam usually entails anyways.
This is genuinely a states issue and not something federal.
Walking very close to someone's home is also illegal with the right to roam. The right to roam just gives everyone the right to walk were they want except in someone's garden. You can also camp anywhere (gardens excluded of course) for a day (or two can't remember) without asking anyone for permission.
One kinda surprising thing is that everyone is allowed to enter fenced animal pastures, provided that they aren't malicious and that they close the gate.
It's an amazing right that should exist in the entire world.
You don't seem to understand that my house, my town, and the majority of my state, are massive amounts of public forest. I have every right to wander and camp, as long as I'm not squatting (which is it's own mess of an issue where what counts "permanently inhabiting" an area), anywhere in that public forest.
Why would my state govt have any reason to enshrine a right that would just make more people trespass because they don't understand the law? Those that follow that law would then have nothing change.
This is why I say it's a states' issue. This won't be the same across the entire US.
There are people who harvest wild food, yes. I think you need to understand that just our national forests are almost twice the size of the entirety of Sweden. Then there are state forests, national parks, and state parks. Texas alone is 50% larger than Sweden, and Alaska is 3x larger than Texas.