Personally I think in order to challenge someone to do something, you should do it too. Then compare notes at the end. You can't fob it off by saying "Oh, I've done it before..." either. If you challenge someone to do it, then show us you can do it too.
I could challenge you to go all Bear Grylls and sleep inside a sheep, but unless I'm going to do it an compare the difference in methods and the successes etc it's pointless.
I think you'll be surprised, food is plentiful outside if you know what you're looking for. Nuts, fruit, plants etc. If you're heading to a woodland you'll be well fed. Got any snares? If you're going near a river then take a net (it's illegal, so don't get caught) or knock up a hobo fishing rod. Air rifle? Pigeons for the taking.
If the missus would let me vanish into the woods for a night or two then I'd be up for this one, but having just got back from something similar then I'm on lockdown for the next 3 weekends
I'm confident you'll find a decent amount of grub to keep you going chap.