"Ik heb gekozen wat ik nodig heb."
Translation:I have chosen what I need.
Mmmm, I'm not sure: require means that you need something for a particular purpose, that it's something compulsory.
need means that something is vital or very important, that it's essential, or that there's a sense of obligation.
As far as I see it, in the case of require the necessity is (externally) imposed, but in the case of need this necessity can be self-imposed.
But it's quite blurry. I don't know, I just wouldn't use require in that context, to my ears it sounds as if it's something you demanded...