The Dutch language
In general, exchange students and students who are enrolled in an international programme in the Netherlands, can get along well in English. In some cases, however, it may be helpful to speak at least some basic Dutch. In any case, you will understand and appreciate Dutch culture better if you understand the language.
Dutch language classes
The best way to learn the language is by taking Dutch classes in your own country and then spending a vacation in the Netherlands before your internship or study begins. The Dutch embassy in your country should be able to tell you where you can follow Dutch language classes. If you follow these up with advanced lessons alongside your study or work in the Netherlands, you should be able to express yourself fairly quickly.
Learning Dutch when you are already in the Netherlands
Ofcourse you can also learn Dutch after your arrival in the Netherlands, for example in a Dutch course offered by the University of Maastricht.
Do you want to study a programme in Dutch?
If you want to apply for a study programme taught in Dutch, you'll need to have a thorough command of the Dutch language. Sufficient proficiency in Dutch may be attained after following Dutch as a Second Language, through an NT2-course. To make sure that you can attend study programmes taught in Dutch, you have to attain the NT2-level II. The NT2-level II exam is a State Examination. If you have no prior knowledge of Dutch at all, it will take you about a year to prepare for the NT2-level II exam.