Green coffee beans typically last around 1-2 years in storage. Given most home roasters store them inside, in climate controlled places, that figure is likely closer to the 2 yr mark. Most green coffee is stored in unconditioned warehouses and lasts just fine for months.

They usually only 'go bad' in that they tend to lose flavor and punchiness over time for most home storage. For warehouse storage in jute bags, they tend to get a 'baggy' flavor eventually which is unpleasant.

Green beans are unroasted, yes. They can last for a long time in storage.