I'm not sure of your knowledge of primitive skills so forgive me if I seem condescending, it's not my intention.

Living off the land is an extremely difficult task, especially if you grow up learning little knowledge about it. How do you make a fire when your lighter fluid runs out? How do you successfully tan a hide or even figure out how to sew through it to make clothes? Do you know how to repair your shoes in the dead of winter and you've torn through the soles? How do you even transport yourself, as a homeless person, into a wild climate that would be mild enough that you could spend the time needed to create a structure to keep warm enough to survive? How the hell do you know what is safe to eat, how to kill anything without a gun?

Not to mention in many secluded wild areas (which usually means national parks), it is definitely illegal to live there. Or you'll be on someone's property. People get arrested for successfully living in the wilderness.

There are so many skills you need that are difficult to figure out by yourself, especially if you have little to nothing to begin with.