If you have an EEA passport (EU countries plus a few others) then you can work within any of the member countries, usually without any serious formalities at all. If you do not have such a passport then you can only work legally in any country other than your own if your country has some sort of bi-lateral agreement with that country, or else you obtain a work permit (usually a permit and visa combined). Language knowledge is an issue for each employer to decide and it is possible that knowing the local language is not an absolute requirement. However, it is most likely that having knowledge of the local language will be required. Be aware that there are plenty of horror stories of young females being promised a job of the type you mention but when they arrive at their destination they are actually illegal and badly treated, including being forced into prostitution.