Did you buy a hosting plan with Dreamhost, or just register a domain? It's not going to work without hosting.
If you have a hosting account somewhere else, you can still register the domain here, but you'll need to change your nameservers to whatever your host specifies.
Here's what DNS Report says.
Save up to $96 at Dreamhost with ALMOST97 promo code (I get $1).
Or save $97 with THEFULL97.