WordPress load javascript file if something… (after the page is loaded)

try now this code

<script type="text/javascript">
function CookiebotCallback_OnAccept() 
{
    if (Cookiebot.consent.marketing)
    {
        var script = document.createElement('script');
        script.src = "https://wordpress.stackexchange.com/wp-content/plugins/instagram-feed/js/sb-instagram.min.js";
        document.body.appendChild(script);
    }
}