Google Analytics has 2 ways to track the metrics of a site: Universal Analytics or Google Analytics 4.0. This article explains more about these 2 options: Universal Analytics versus Google Analytics 4 data

Universal Analytics uses a UA ID, whereas Google Analytics 4.0 or GA4 uses Tags. 

To install Universal Analytics, follow the instructions on this article: Install Google Analytics Tracking

To add a Google Analytics tag you can use a widget called: Bootstrap Theme - Google Tag Manager Code widget

To edit this widget and add the code go to:

Toolbox > Widget Manager > search for: Bootstrap Theme - Google Tag Manager Code widget > Edit: