The light could not reach us yet. If you have an infinite universe, you cannot see for ever. You can only see 15 Billion light years and not more. We have a finite observable universe. This resolves Olbers'Paradox.
Space is expanding like the yeast dough, dough is finite.
You cannot know the center, but you can talk about the center as the observable universe. We cannot send information through space, which travels faster than speed of light. We don't know whether the universe is accelerating or decelerating. A universe full of masses has gravity. We measure the escape velocity.