If harvested once they’re fully ripe, you should be able to store winter squash for several months… try to wait until the leaves start to die off and the stalk has turned brown and dry, and the skin hardens, before harvesting them as this helps them to store longer. Once harvested, the best thing to do is keep them in a warm and dry place in the house…you could go for a sunny windowsill, or just at the back of the kitchen. They should keep for months, if you’re lucky, they’ll be ok up until April or even May next year.