I just wondering is there any warning light indicate the boot was released??

Because last time, after I parked my car, I find out that my boot was released.

That's not safe if the boot was reseased while driving as well as not safe while the car was parked.

No, there is no "trunk ajar" light, which is one of my few minor complaints about the car.

But while there is no warning light on the dash, the alarm will tell you indirectly - if any of the doors, hood or trunk are not closed properly, you will not get the confirmation flash of the blinkers when you lock the car. (The flash indicates that the alarm has been armed, which won't happen unless everything's secure.)