Under normal circumstances, a PhD track will take four years. There are various kinds of PhD candidates. Some candidates are employed by the university, but others bring their own grant, for example a teacher’s grant for high school teachers who execute PhD research. The faculty also has a large number of external PhD candidates, who work part-time on their research. The website of VU Amsterdam regularly features vacancies for new PhD positions at the faculty, for which you can apply. On Academic Transfer, PhD positions are also advertised.
If you are interested in doing PhD research, you would do well to look first into the Departments of the Faculty of Humanities, to see which specialisation best accommodates your own interests in scholarly research. You can contact the researchers directly or via the Graduate School of Humanities, to review the possibilities.
Are you curious what doing PhD research at VU Amsterdam is like? Read more about it on the VU Amsterdam's website.