After you create the Cloud DNS Zone on Google Cloud Platform, you will need them later in order to run your website properly on Google Cloud Plateform. For example, you will need the name servers when you set up the domain name.
Step 1: Login the Google Cloud Platform and click the menu icon on the left-top corner in the dashboard;
Step 2: Click "Network services" from the left navigation menu;
Step 3: Click "Cloud DNS" from the menu on the left;
Step 4: Click on the domain name you want to get the Cloud DNS Zone;
Step 5: You will see the name servers right in middle of the page.