About 45 years old, female, with high school education, what skills do you need to learn before immigrating to the United States?

First of all, you have to learn English well, or the people who write about the embassy will not give you a visa. Secondly, people with high school education in the United States will not have good jobs. I suggest you save more money, open a restaurant there and cook some China-style food, such as jiaozi, steamed stuffed bun and so on, to earn more money.