Please refer to https://v2.developer.pagerduty.com/docs/send-an-event-events-api-v2 and https://www.zabbix.com/documentation/7.4/manual/config/notifications/media/webhook#example_scripts.

Set global macro {$ZABBIX.URL} with your Zabbix server URL.
Add a dedicated user with the media type "PagerDuty" and place the integration key in the user's "Send to" parameter to integrate into the service.