travel from dublin to san francisco custom and border protection office by train please advice route and stree

Answer 1

There is a dublin in bay area, only 30 miles away SF.

Or you mean dublin, ireland?if so, exit flight and pass though custom service, you will get a visa stamp in your passport( suppose you are irish citizen) and you will fill out a form to clear if there are somethings illegal or duty cost items, otherwise, you will fine.

Walk out international terminal, take BART( subway system) to downtown( powell station) hotel or hostel for $5.15 and 35 min ride.