Write about what it's like to be YOU.
Are you saying you have done absolutely nothing in the 12 years you've been alive?
You don't need to have emotional stuff attached. Just the facts. You must have done something, gone somewhere, learned something new, had scary moments, etc. Relax and stuff will come up for you.
I see. Did your teacher actually use the words "deep in emotions?" or does it just feel that way to you? The truth is, you are probably a little paralyzed by the word. It's a little scary for a guy your age. I believe if you try and not think of the emotional part of this and just write, you'll find the emotions come naturally. You can do this.
I apologize if I assumed you were a guy...you might not be. Anyway, I repeat, relax and remember and it will come to you.