If you're lost in the woods with nothing, you don't start to look for food.
You can live without food for 3 weeks, and if you happen to eat something wrong, you can get violently ill or poisoned.

Here's what you do:
First you try to call for help, or wait for help, if you know someone is looking for you.
If not, you start to walk downhill (even if it's just a barely noticeable slope).
At some point you'll find water (a creek, river, whatever), or at least a dry river bed.
Then you follow that downstream until you're literally out of the woods.

That way you aren't in danger of walking in circles, and rivers generally lead you to settlements.
There's hardly any spot on earth left where you won't reach the nearest settlement within a week (i.e. before you die from hunger) that way.