Are humans allowed to live wild in the USA and Canada's?

Unlikely unless they do it in a rogue way. All property is deeded to someone or some entity so unless they own a good sized piece of property it’s unlikely and even then they must pay property taxes every year and come up with the money to do it unless they have a relative or friend that owns property and would allow it. One of my favorite movies is Last of the Dogmen, I would highly recommend it even though it’s a fictional movie it gives a concept of how it would be.