A clay pot requires skills and potentially hard work to make, since you need to dig a lot if there is no clay deposit or river near you. Training fabrication and others until you can craft it, will take some time, too and you are probably dehydrated until then.
Unfortunately you can not use tin cans for boiling anymore since 0.F, but maybe a new item would make sense here.
I could imagine some makeshift cooking vessel which is essentially a can with a hole drilled into it so a stick can fit into there.
The reason why you can not use cans for boiling anymore is probably because they have no handles and are too small for a normal fire to be placed in, so they will be searing hot.
Essentially transforming the can into a tiny pot can help but it will be tedious to cook with it. It will save you in an emergency but that is about it.
The current situation without any additions would require eating foods that can hydrate you, like berries. But this is going to become harder if you do not start in the summer. Finding eggs in the bushes will also provide some hydration, even if you have to eat them raw.