How To Verify with Google Webmaster Tools/Merchant Center
If you sign up for a Google Webmaster Tools or Merchant Center account, Google will ask you to verify that you are the owner of the website. Opt to verify by adding a Verification Meta Tag to your website, and enter the Meta Tag into the box in the Marketing > Google Tools > Webmaster Tools section. Once verified with Webmaster Tools, you can submit your Sitemap URL to help Google index your store and improve your chances of appearing in their search results sooner. You can find your Sitemap URL at the bottom of the Marketing > Google Tools > Webmaster Tools section.