It is most likely a dead battery, especially if there is no power for lights or the radio. Check and clean the battery terminals because corrosion can break the electrical circuit.
Does it turn over? Does it turn over?
It is to give the starter enough power to turn your car over to start it..
Car won't start... engine can turn over, no power.
Check the battery and connections
Could be the ignition switch, the starter, a faulty wire, the battery...
replace the starter
Bad starter or weak battery.
Maybe more information is needed to answer this question. Does anything happen when you turn the key? Does the motor turn over but not fire? Does the motor kick but not run?
What do you mean it wont do anything... will the engine turn over... is the battery good... if the battery good and the engine wont turn over as if its not receiving power to the starter then it might be a bad starter or bad starter solenoid.
Does the engine turn over and then make the clicking noise while trying to start, or does it not do anything but make the clicking noise when you turn the key. If its not turning over at all then it might be a battery problem, Try cleaning the battery terminals, and/or charge the battery, Could also be the starter solenoid, but start with the battery first.
First place to start obviously battery-check voltage. Even if you have "some" power it takes almost 10 volts to turn your starter
Will turn over but will not start