My first day at job location and did terribly? My coworkers don't like me. What do I do to get along (x long)?

Workplace 'hazing' is considered harrassment. I'm sorry you have to work with such immature people. You seem to have a connection with your old boss, maybe you should talk to him about the situation and see what options are available to you within Starbucks. If you never speak up, they may never know what's going on.