What are the solutions for UTM-based content substitution?

Question

Content

The goal is to serve a modified version of the web page to the visitor based on the UTM tags in the URL. The content that can be changed can be multiple: phone numbers, city, titles, order, and presence of blocks.
The problems are:
+ Keeping records of the changes that will need to be made to the web page in accordance with UTM
+ Replacing elements on the web page in accordance with UTM
PS: I saw this question / answer toster.ru/q/88897, it I'm not satisfied with its PHP'shnost and not understanding how to store records.

Answer 1

if($_GET['utm_source'] == 'yandex') { // контент site.com?utm_source=yandex 
    }else{ 
    // контент если не существует UTM-метки
}

And by the same principle