If the player gets hit by an enemy plane more than 3x, the player loses a life and the main plane should be destroyed
If the enemy plane hits the main plane, we want it to do some damage.
Add a Collision with enemy1 event...
Go into your room. Have just enemy1 controller.
If it works, in the myplane object, duplicate the Collision with enemy1 to create the events for when the plane collides with the other enemy planes.
Go into your room and add enemy2 and enemy3 controllers.