How to configure alert actions?
Splunk already has a set of pre-defined alert action that you can use OOTB:
https://docs.splunk.com/Documentation/Splunk/latest/Alert/Definescheduledalerts
Or you can create your custom one, using some python and configs files, if no one suits you:
https://docs.splunk.com/Documentation/Splunk/9.1.0/Alert/CreateCustomAlerts
I suggest the follwoing docs link:
The necessary actions depend on whether you are running Splunk Enterprise or Cloud and the differ depending on the type of alert.