If you bought them online they should have sent you a confirmation email. I don't know who you bought them with but the email should have a confirmation number or a QR code. There is a ticket place at the pier that should be able to help you.
On your phone when you enter the pier.
Pier 33 it's called alcatraz tours
If bought online an email is sent with a code,when you arrive at the podium the person will scan your tickets for you to start getting in line.... Hope you wear comfortable shoes and have fun
At will call at Pier 33
Thanks! Your answer is awaiting moderation.