it has to thaw out and drain before you do anything. i believe the sound is the motor unable to turn because the water pump is frozen solid. when it freezes like this, ice expands and could crack the bloc. you wont know till it is drained and coolant installed and see if it runs and holds pressure.
once again, the petcock may be too small of an outlet for the water or ice to escape. remove the lower hose form either the radiaot or the motor and let it hange till it thaws. is the temp up enough for the ice to thaw?? if not, then you need a garage to help the process.
You have to get the anti-freeze into the anti-freeze tank which is a clear tank in the car near the engine. Also if the car won't start, it could be the battery might be dead. So take your car to your local mechanic or dealership and they will replace the battery for you, which will cost you between $65-150 depending on what brand they use. Also, have them check all of the other fluids in the car besides the anti-freeze and they will fill them up for you but that will also cost you between $25-50.00. Hope this helps and good luck.