The reason we are in a place that is perfect for us is that if the place wasn't perfect for us then we wouldn't be here. For instance, the biological processes that began life on Earth did not start on the Sun because they would have got all burned up before it got started.
This has nothing to do with the Big Bang theory because this theory tries to explain the process that lead to the configuration of the universe today, why there are planets like ours that have properties that can sustain life, and why there are suns and stars for instance. It may not be correct but currently it is the explanation that most comprehensively fits the facts we have observed.