What skills or knowledge should I learn in the first half of working abroad?

You don't have to learn technology. First of all, you must be able to do housework, cook, wash clothes, fold quilts, hang clothes, and so on at home. To put it bluntly, you must know all the housework your mother can do. So I have time to work and accumulate some experience. This is very important! Because even a part-time job abroad depends on whether you have any work experience. Working abroad, foreign students don't need many skills, because their main task is to study. When they are at home, they will go out to hone themselves and be well informed. No matter what they do abroad, they will not suffer. If you really want to learn, learn from a barista. It might be useful. Foreigners seldom invite China people to their shops.