Hello,

To achieve this you need to do the below:-

Hello,

1. First create a new email script with below code:

(function runMailScript(/* GlideRecord */ current, /* TemplatePrinter */ template,
/* Optional EmailOutbound */ email, /* Optional GlideRecord */ email_action,
/* Optional GlideRecord */ event) {

var url= 'Add the Url of the Portal';
template.print('<a href=' + url + '>text you want to display in the mail </a' );
})(current, template, email, email_action, event);

Screenshot:-

2. Go to the notification HTML message and add the below

${mail_script:<name of the above email script>}

Screenshots:-

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