Step 1: Add the Global site tag to your header code by adding the gtag snippet to your existing Google Analytics code.
Step 2: look for the "onclick" code and paste the code where your button is on your website.
<button onclick="return gtag_report_conversion('http:/
<div><a class="btn-primary" href="/contact">Contact Us</a></div>
change to
<div><a onclick="return gtag_report_conversion('/contact')" class="btn-primary" href="/contact">Contact Us</a></div>