Google Tag Manager is used for website tracking and analytics. By creating a connection between your website and Google Tag Manager, marketers can create tracking tags for various purposes on your website without needing a web developer to install and update code.
Google Tag Manager can be added to your WordPress website a number of ways.
As a requirement is to add a piece of code after the <body> tag, it depends on how your theme is set up on the best way to do this.
One option is to install a plugin from the WordPress plugin repository or contact your web developer who will install two small pieces of code on your website.
Contact Webtree if you require assistance integrating Google Tag Manager with your website.