Your body can go 3 minutes without air, 3 days without water, 3 months without food...u can go longer than 3 months but your body will start to corrupt and your system will not be able to digest...
If you're lucky you can survive up to 3-4 days without water.But usually it's 2-3 days. With water intake and doing no heavy physical a man can survive 30 to 80 days ,People of the Jain religion...
Crayfishes can surive 2-4 days with out foodIf you were about to go on a vacation for about 2 weeks you can put in alot pieces of apples(tiny pieces) and they could surive