Is your post or page a few public function? Then, use the Occasion style to markup your metadata. Here are all the fields that you should see when using the Event Schema in your article. The initial step is to add structured markup to your website. You can search for https://www.presta-addons-modules.com/en/opencart-seo-automatic-google-rich-snippets-json-ld-integration-opengraph-twitter-tags-schemaorg.html