If you meet the criteria, you indicate in Studielink that you wish to pay with a proof of paid tuition fees (Bewijs Betaald Collegegeld).
Follow the steps below:
Not a student at the UvA yet? You can find the right contact information on uva.nl.
Do you have general questions about studying at the UvA, for instance, about your enrolment or tuition fee? Contact the CSSD.