2001 M3 Overheated

Hello everyone

I'm new to the site and hoping you can help me out.
I did the most stupid thing yesterday.
After not starting the car for months, I thought yesterday I would start the car for a few minutes to to charge up the battery.
The car started just like it was new. I let it run for a few minutes and I was then distracted and went on to do other things totally forgetting the car was on.
The car must have been running for at least 6 hours in the garage. The worst thing was I didn't take the car cover off.
After I remembered the car was on, I went into the garage to find all the blue fluid on the ground. The ignition was still on the on position and the car was not running anymore.

I took the key out and didn't touch it any further since it was incredibly hot.
The engine compartment was all white from what I'm guessing is fried antifreeze.
What are the chances the engine is cooked. It's killing me because the car has only 43,000 kms on it.

Thanks

2001 M3 Overheated