As you already know a new version of Google Analytics was introduced in October 2020 that requires the usage of a Google Analytics 4 (GA4) property to track unified web and app analytics. More details on the differences between GA4 and Universal Analytics (UA) are available here.
This article will guide you the ways to upgrade your existing Universal Analytics (UA) to GA4 via the Site Kit WordPress plugin.
Beginning with version 1.36, released on July 7, 2021, Site Kit is adding the ability for users to create and add a GA4 property directly through the Site Kit interface.
Steps to set up a Google Analytics 4 property alongside your existing Universal Analytics property
Click GA4 Setup Assistant (instructions below) to create a Google Analytics 4 property that collects data alongside your existing Universal Analytics property. Your Universal Analytics property is left unchanged and continues to collect data — you can always access it via the property selector or Admin screen.
If you use a website builder or CMS-hosted website (for example, WordPress, Shopify, Wix, etc), use your website builder’s/CMS’s custom HTML feature to tag your site. Follow these instructions. Do not simply paste your “G-” or “UA-” ID into the field that your CMS provides.