Although you can easily get by in the Netherlands without any knowledge of Dutch, it may be useful to learn the language if you plan on taking the citizenship exam (inburgeringsexamen). It can also give you more options while looking for jobs.
Some universities have language centres that offer courses to students at a lower price or for free. Make sure to check with your university whether they offer this option! If not, there are many private language centres and tutors who offer packages with fixed prices for different levels.