The battery in the boot/trunk is indeed the starting battery whilst the one under the seat works the ancillaries and, when the rear battery is dead, can start the car if needed subject, of course, to it being charged!
There are two terminals under the hood in the right hand corner of the engine bay when looking at the engine whilst standing at the front of the car.
Read the manual reference a jump start.
You shouldn't have left the key in the ignition. Always lock the car properly and put the keys somewhere well away from the vehicle so it doesn't keep "waking up".
There is a very tiny hole near the key. Insert a straightened paper clip and it should release the key.
There are two terminals under the hood in the right hand corner of the engine bay when looking at the engine whilst standing at the front of the car.
Read the manual reference a jump start.
You shouldn't have left the key in the ignition. Always lock the car properly and put the keys somewhere well away from the vehicle so it doesn't keep "waking up".
There is a very tiny hole near the key. Insert a straightened paper clip and it should release the key.
