What is the religious ruling regarding a Muslim woman working in Spain in fields such as childcare, or as a domestic helper (live-in or hourly), or caring for elderly women (live-in or hourly), or washing dishes in restaurants and cafes (which may serve alcohol or pork), or as a cleaner in hotels, to help cover her medical expenses and daily needs, taking into account the difficulty of finding work there that meets the conditions of Islamic Sharia?

A Muslim's residence in the land of disbelief is permissible out of a legitimate necessity, and the duration of the stay is determined by the extent of that necessity, provided that the Muslim safeguards their religion. Therefore, there is no impediment to the questioner's sister residing in the lands of the disbelievers for the purpose of medical treatment, and then returning to the lands of Islam once the necessity ceases.

As for a Muslim woman's work, it is conditioned upon the work itself being permissible. Thus, it is not permissible for her to work in preparing alcohol, pork, or anything related to them. It is also conditioned that there be no private seclusion with a non-mahram man, no uncovering of any part of her awrah (private parts), no mixing with non-mahram men, no exposure to temptation, and no humiliation through serving disbelievers. If the work is free from these prohibitions, then it is permissible for her to engage in it.