I would set the robots meta tags to "noindex,follow" in a static page.
For Magento 1.9 I used to do it like this:
<reference name="head"> <action method="setRobots"><value>NOINDEX,FOLLOW</value></action> </reference>
How to do it in Magento 2?
Magento Stack Exchange is a question and answer site for users of the Magento e-Commerce platform. It only takes a minute to sign up.Sign up to join this community
You can set it admin. for magento. For Magento 2.1 & 2.2 Go to Content > Configuration. please edit your theme .you can see your screen as attached screen shot. i have highlighted seo robots section. : https://i.stack.imgur.com/cP1Si.png
For Magento 2.0 you can check here : https://www.mageworx.com/wiki/magento-2-robots/