Okay so i will b going away for a day, and I want to have my villagers not die, but I need them to advance in the game, so would it be safe to leave them with a 2,135 food in the bin?

Or would they all die?

If it's just a day, you should be okay. If you want to be extra sure, you could always change the speed to "slow" to make sure that they don't eat all of the food quickly. You'll also want to make sure you have a trained doctor to take care of any illnesses that might happen while you are away. If you still aren't sure they will survive, the best bet would be to pause them, even if they don't advance. Better to have a slow village than no village

Okay, thank you, right now mine is on fast

Additionally, you might make sure you have a few (perhaps even several) trained farmers who can continue getting food while you are gone. If it were my game, I would definitely change the speed before going away for a day. I hope this helps you!