When we turn key car is dead. Car has been sitting for 2 months.

Replace your battery, a battery discharges every day you dont run the alt. to charge it up... after a week or 2 weeks the battery would be dead, just from a car sitting not being started... if you are not using the vehicle, it is a good thing to replace the battery, and every couple days just start the car up and let it run a while to charge the battery.... if you are going to have to leave the car for a while without starting it, then disconnect the battery, and remove it from the vehicle... you can buy a cheap trickel charger for the battery when it is out that will keep it charged till you decide to put it back in.... hope this helps you...