As you face the basilica, it is at the left, beyond the left arm of the Bernini’s colonnade. Sometimes, when there is a very large audience, St. Peter’s Basilica, or St. Peter’s Square, the large explanade embraced by Bernini’s colonnade, are used instead.
Anyone can have access, yet you must obtain first a free ticket from the Prefecture (Prefettura) of the Papal Household, which is situated past the “Bronze Door”, where the right arm of the colonnade begins (as you face the basilica). It is open Mon. – Sat. between 9am and 1 pm.