Car registration

Hello,

I have recently moved to the country (Flanders specifically) from another EU country (Hungary) and I’d like to have my car registered in Belgium. The car is road legal of course, and already has a valid Hungarian license plate.

I tried to request an appointment to a nearby DIV office online, but the website is asking me to provide a number from some form that I was either supposed to receive, or to fill out – the instruction isn’t very clear. I have no idea what this form is, where to find it and how to fill it out.
The images provided refer to the data I’m asked to provide, in Dutch and in French as well.

I just want a belgian license plate on my car, that’s all. Could someone be so kind to walk me through the process step by step?

by TwoBasedFourYou