How can this electrical problem be fixed

I own a 2003 Oldsmobile Silhouette. All the dash warning lights etc stay on while driving down the road. All of the gauges such as fuel and speedometer are not working. The Radio is not working as well. All this happened while driving down the road. Again I can drive the van fine but do not know how fast I’m driving and how much gas I really have. Any ideas what this could be?