Tried jumping it? Often clicking from the starter solenoid is a sign of a drained battery (too weak to even crank at all). If it jump starts then you will know it was the battery, and you can take it up to any parts shop to have the battery (as well as the entire charging system) checked.
If you try jumping vehicle and it still does not start tap on the starter with a hammer while someone else starts vehicle at the same time if vehicle starts starter needs to be replaced. That is a test that works sometimes if it does not still can be a bad starter.
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