Hamas has hundreds of thousands of liters of fuel for vehicles and rockets; caches of ammunition, explosives and materials to make more; and stockpiles of food, water and medicine. militants, estimated to number between 35,000 and 40,000, had enough stocked away to keep fighting for three to four months without resupply.
One of the sraeli hostages released by Hamas described militants providing captives with medicine, shampoo and feminine hygiene products.
https://www.nytimes.com/2023/10/27/us/politics/palestine-gazans-hamas-food.html?smid=nytcore-ios-share&referringSource=articleShare