My car won't start. why?

My car was starting immediately and driving fine. Now it won't start and the oil light is on. I added oil. It still does not start, does't make any sound when turning the ignition, and the oil light is still on. The other electronics come on, radio, light etc. Also, the batterie is about 3 months old.

I just bought this car. The previous owned passed away, so I do not know more about the recent history.