Will my car battery die while I'm gone for three weeks?

My car is Honda Civic 2015. I purchased this new car in October this year. I wonder if my car battery will die if I leave this car for three weeks in the airport parking lot while I'm away?

Your battery should be all good, unless you leave lights on or something (but I think it will turn them off automatically after a minute or two anyway)

It won't die.

It may be a little weak, but unless you leave something plugged into a power point like a GPS Navigator, or a cellphone charger, etc, you are not likely to have a problem for a few months. Cold temperatures are less of a problem than hot climates for batteries. Worst case, have jumper cables in the car - which should be part of any emergency kit to keep in the car anyway, along with a ice scraper and brush - if you're in the Northern Hemisphere, winter is here, and likely to see snow and ice needing to be cleared before you can move the car.

If it does, it needs replaced anyway. You should be able to park the car for at least 6 months at a time without issues.

Probably not, but buy a portable booster just in case. You might have to use it 10 years from now, or find it useful getting someone else going who has blocked your way and has a dead battery.

No, three weeks is not a significant amount of time in that regard.