To give you an actual answer, and you will probably not like this answer - you eat everything. Eventually. And it won’t end well.

You have only your hands, so you won’t catch any meat. You could try to make tools to make traps or catch fish, but that’s really hard.

For the first week, you probably won’t eat much at all. The hunger will fade after the first 24 hours. But after a few days it will come back, and it will come back strong. You’ll do what babies do - taste everything.

You won’t have tribal knowledge passed down, so you’ll rely on the backups - smell and taste.

Put a little bit of whatever it is in your mouth. If it’s bitter, spit it out. If it makes your mouth tingly after a few minutes, spit it out. Otherwise, swallow it. Wait an hour. If you’re still alive, and feel okay, that thing is probably okay.

You’re going to eat lichen, moss, tree buds, flowers, lots of roots, and strange berries. You’re going to turn over rocks and eat grubs and worms. You’re smart enough to shy away from mushrooms - at first.

Eventually you will be so incredibly hungry, and you will see mushrooms with mouse chew marks, and you’ll think to yourself: “if the mice can eat it, so can I!”. You’ll probably be right, and regardless, the gamble between a new food source and death will seem like a win-win.

Eventually you will get it wrong, and it will hurt the entire time that you’re dying. Life sucks. Your best bet is a few lucky guesses on something relatively abundant so that you can stop guessing.

Longer term, eventually you will figure out those tools you were attempting between foraging runs. Even longer term, you will re-invent farming, and even might not die of a vitamin deficiency. Good luck!

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Practical answer: don’t do that. Ignore food. Get rescued. Go downhill. Most of civilization is on the coastlines and/or riverbanks.

And drink the water! If you only have gross water and no way to filter or boil it - drink it. The difference between death by dehydration and death by bacteria is about one to two weeks, which is more than enough to be rescued. The hospital might be able to fix you sick. They can’t fix dead.