Stay by the edges and kills some draugers... make a tree fort on the edge but on a good side if you are getting killed and shoot down on them.
Drauger drops sausages a great food you will use for a while.
Carrot soup you should have already. Make a cultivator so you can plant seeds.
Turnip seeds are another thing you want to scout the edges of swamps for. They are fairly rare but all you need to find is one plant for seeds and you can grow them.
Those three can carry you through the swamps and past the mountains.

Once you get iron you can do pretty well serpent hunting as well for serpent stew.. that is "end game" food at present.

Sausages, carrot soup and whatever at least can make searching the swamps a bit easier.

Make a cauldron out of tin to cook stuff. Berries can get you queens jam you can use till you get turnip stew. Oh I guess if you have poison resist you have a cauldron.