UK, Ireland /
Advice for my Polish friend who came to the UK to work [22]
I would recommend he learn English. Pronto! Without that he will have a difficult time finding a good job. Even in Chicago, where many do speak Polish. It's best if he comes on a B-visa, which is a work visa, then he will be here legally, for a while at least. Did he come on a tourist visa last year? If so, he was lucky, they are hard to get. The work visa is easier and quicker to get.
But since he's been here last year, he became familiar with the US a little, so he won't have that big of a culture shock. If he feels scared, you can assure him that he can go back anytime and that many people leave their home country behind for a different life, some leaving spouses and children. He's still young. A whole life ahead of him.