I was told my 08 Buick Lucerne needed a new fuel pump" I replaced it cranks but still no start" I DONT HEAR THE FUEL PUMP WORKING WHEN I TURN THE KEY EITHER" What should I do next I checked all fuse

Could you hear the original one run? It can't hurt to replace the fuse but without a float how will your gas gauge work? It sound like they sold you the wrong pump.

Here's what you should have .... I had a problem with one that a guy brought in that he only replaced the pump but he only used a compression fitting on the outlet side of the pump when he should have used a Hose clamp ... after a few days it quit. We took it apart (Man --- GM makes that job a "piece of cake" when the put that access where they did) The pressure side of the hose blew off inside the tank and of course no pressure ... no run. Notice the fuel level on the bottom