How Do I Add the <Meta> tag into <Head> on a Page?

You can add meta tags for a specific page in the page settings. To do this, right-click the page and select Settings. Then go to the "Custom Code" tab, click on the "+" icon, and select <meta>. Screenshot:

After that you will need to give a name to the code that you're placing and then fill in the fields based on your meta tag. Here, for example, I added the Google Search Console confirmation meta tag:

Before, this meta tag looked like this: <meta name="google-site-verification" content="b8YFL2KcrU34LSknA1CCdnzsVm2yYaYwEjrrrFRSyLg" />