Is it permissible for a wife to remove her hijab to work as a teacher in a European country to meet the family's needs, given the husband's illness and the absence of another provider?

A wife must stay in her home to raise her children, and it is not permissible for her to go out to work if that entails a Sharia-prohibited matter. The husband is responsible for financial support, not the wife. However, there is no harm in her assisting him if her work is suitable and does not lead to Sharia-prohibited matters such as intermingling (free mixing) or abandoning the hijab. It is not permissible for a wife to work except in cases of extreme necessity where no other means of livelihood is available, for "necessities permit the forbidden."