If you hear a clicking, thats the solenoid engaging to direct power to the starter, but if it's not turning, theres a problem with not enough power for the strter to turn.
Most likely low battery power. Even if the charger is connected, you have to let the battery build up enough juice before the starter will turn. Step-by-Step to check
1. Charge battery fully. Try to start.
2. Check battery connections, make sure they are clean adn the clamps are tightened for positive connection.
3. Check for good ground connection to block. Or shortcut by creating a jumper for ground: take a set of jumper cables, connect negative clamp to neg terminal on battery. Connect the other negative clamp to metal accessory bracket. Do nothing with the postive clamps. Try starting. If the car starts, you have bad ground cables. If it still does nothing but clicks, grounds aren't the problem, next step
4. Check postive battery cable and connections to solenoid (on driver side fender) and connection to starter (under passenger side on transmission). Clean connections/replace cable if required.
5. Remove starter and test.
6. If you get to here without finding the problem, you're buggered
. Check back in, and we'll continue with other possibilities.