I am basically a Military Commando i have remain personnel Gun man to0. what should the real role of a close protection observer in case of emergency?

You must first assess the nature of the emergency, and to secure your site

I'm a soldier who was trained in the middle of war, my trainings are for taking the descisions depending on how the situation is. 

first of all in case of an emergency, you should first assess the nature of the emergency, secure your location and get your tools ready to respond, communicate to your authority for instructions on the course of action that is if situation permits if not use your discretion and neutralize the threat if your life and the life of those you are protecting is in imminent danger 

more Traning and eat the meat :D hhhhhh