[consilient]

> today’s observable universe is roughly 13.8B years. By the time you travel to the edge of that universe, others stuff has travel from that edge to even further position at various speed including faster than you do.

This is true but it's not what astronomers mean when they say the universe may be infinite. They're talking about the whole universe, not the just the observable part, and they really do mean actually infinite in extent.

> before/at big bang universe is a single point.

Unlikely. We know that what is now the observable universe was very very very very very dense. Predictions of a literal singular point are the result of extrapolating past the point where we know for a fact that our best physical theories break down.