Do I need to worry about such things?

I will go to Philadelphia to attend a conference next month. My supervisor told me to go by myself and she would not accompany with me. Honestly, I am very lacking of in confidence about my oral English. Recently I am always thinking that wondering whether I will meet with a lot of difficulty just because of language. For instance, when I go to a restaurant, the waiter will ask me to order and  maybe I am will not be familiar with the words used in the menu, and it must might be very embarassing that I do not know how to choose from the menu. Who can tell me do if I need to worry about such things for on my first time to go visit to the USA? If I really meet with the occasion encounter a situation that I cannot understand others or they cannot understand what I want to ask, what can I do to resolve all the problems? The lack of confidence of in my oral English really makes me worry about this visit in to Philadelphia.

I do not think you need to worry so much. Philadelphia is a multi-cultural city that is visited by many foreign tourists. The restaurant employees are accustomed to serving non-native English speakers. If you have problems understanding anyone you can also ask them to speak more slowly, or perhaps write down what they are saying. If you have a smart phone, you can always use a translation site to help clarify any language misunderstandings.