At this point I feel obligated to say that the other characters that you met inside of the building are other players connected through the Internet. Well back to the story.
As you get outside you start to hear the sound of your stomach screaming for food. (There is a in game meter that measures your hunger state. If the meter reaches zero you will DIE.) The first thing you have to do is to look for food, unless you found food at your starting location. If you did not find any food at in the starting building you will have to break in to another building to search for something to eat. Fortunately the hunger meter will not reach zero rapidly so you might explore the environment instead.
Regardless what you decide to do you will shortly find out that you are not the only ones looking for something to eat...