Upgrade and farm new foods : top black forest are in the cauldron deer stew ( cook deer meat , blueberies and carrot ) , minced meat sauce ( boar meat , neck tail and carrot ) and carrot soup ( carrots and red mushroom )
With that youll be very OK , when explore swamp go for draugr guts to make sausages , kill leechs for blood bag to make black soup and farm turnips to make turnip stew . thats the top food in the swamp upgrading the cauldron to lvl 2
Gear , i recommend troll armor lvl 3 and bronze buckler ( block at time to parry ) until farm good numbers of iron and make full iron set at lvl 4 , with this gear you will not feel pain in the swamp
Oh and make a lot of anti poison me/ad at the cauldron