Well.. we die because our body gets older meaning our cells and it can't repair itself anymore. If this can be effectively stopped we can live forever, the reason we die (naturally) is because our cells deteriorate over time. Find a way to effectively stop this and you will live forever if you don't get murdered or have an deadly accident or catch a disease that kills you. Or if you would kill yourself...
Yes but when the sun dies, we'll die. And if we escape somehow and manage to survive, something will kill us before "forever" is over...
You know my only dream is to be immortal.. I somehow believe that science one day will defeat death...