One thing I find about being autistic is that it does make you very single minded. I have got an allotment but the slugs seem to eat more of the produce than I do, I am not at all sure that it could provide enough to survive however but it sure as hell provides more than huntin and fishin, not that there are any fish in the local river to be caught and I would have to eat cats and rats, or maybe squirrels. No shooting is allowed on the plot though. I really don't see how any one can survive in the UK if they do not have somewhere to grow crops at any rate. Ironically there are areas of land even in dense urban environments where, if you had an accident you might not be found for years. I am in adverse possession of just such a piece of land, I would not want to live there though, I would not last long. In high summer I can stand in the middle of it, in earshot of the housing estate and the allotment but nobody knows I am there. There used to be a man in Coventry who lived on his own in a piece of Council woodland, nobody knew his name and I have no idea how he survived, but he did. https://medium.com/adams-notebook/mr-tuesday-in-wainsbury-woods-4eea998554fd