1994 Chevy Beretta Coolant

That is correct. Never open when hot. Also the radiator cap is located at the same area where you have to stick you fingers in to open the hood. Once you open the hood, look towards the left slightly or it may be right there in the middle. That cap is your radiator cap that is where your coolant goes, it should be full. Also your gauge may be at hight temp but that does not necessarily mean its overheating, the sensor for the coolant could be gad. So top off you coolant and let me know what happens