Honda CRV. If the alternator stops working and the battery isn't charging, should this affect the brakes?

Honda CRV. If the alternator stops working and the battery isn't charging, should this affect the brakes?

The brakes should still function, since they use a hydraulic system.

But the anti-lock brake system might not work properly because it uses electronic components and sensors.

Low voltage can cause the "brake" warning light to come on. Its warning you that the system doesn't have enough electrical power to run the anti-lock brake system properly. If its just low voltage then the light should go away when the alternator is replaced and the battery recharges to sufficient voltage.