Set your opening date in Google Search & Maps using a Computer: Go to your Business Profile. Learn how to find your profile. To edit your business information: Using Google Search, click Edit profile. Using Google Maps, click Manage your Business Profile Edit profile. Under the “About” tab, click Opening date. Enter the required fields. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.