In the dynamic page SEO settings, you can set
• Meta title
• Meta description
• Social cover
dynamically for each CMS item.
First, make sure that the page you are going to set up is a "dynamic page" and that the SEO settings are set to Page, not Site.
To make the Title and Description dynamic, click the + icon and select the appropriate property. You can also add a string that you want to fix to any item.
To set the SocialCover, click on the property displayed and select it.
Once you've set up the above, check it in the live preview and publish (update) the site if it's OK.