There is a clicking sound in my 1997 dodge caravan

Sounds like you might have a bad battery cable/s and or connection if your lights are not coming on. Make sure connections are clean and tight at both ends of each cable. Positive - from battery to the starter. Negative - from battery to the engine.

The clicking sound is the relay in activating mode, but there is not enough current to crank up the starter. The terminal cables connecting to the battery poles need to be cleaned so no high resistance limiting current flow from battery to the circuit. If you don't have enough current flowing into the circuit,starter is not cranking, head lights are not on, horn is not working. Use the sand paper to clean the inside ring of the cable terminals until they look shinny then put them back, you are good to go. Measure voltage across battery terminal with the volt meter. It should be more than 11.8 volts without the engine on. With the engine is on, it should be more than 13.0 Volts to ensure alternator is working.