It appears you are trying to set name servers for an external web host. You need to find out what the name servers are for your web host and then set them in the name server settings. To do this, please follow these instructions here:
How do I set my name servers for my domain? http://www.dynadot.com/help/question.html?aid=3
Please note that it could take up to 24 hours for the changes update.
If you have any other questions, please let us know.