There are two types of terminations you can perform on users.
Step 1. Simple termination
One can user the Terminate user or Delete feature, described in the document by the link. This feature changes the user status to Terminated in OpenIAM and sets an end-date on all entitlements across all connected applications.
Step 2. Common customer case
A very frequent case is when the user needs to be terminated in OpenIAM, but moved to a disabled OU.
Here, one can use terminate user feature in the workflow. To access it got to webconsole -> System configuration -> Workflow and choose Terminate user in Default Approver Resource line.
Here, you can terminate users in OpenIAM and set the end date for entitlements or you can terminate users and remove the entitlements. Any case will trigger the removal process in the target system(s).
However, if you need to move users to a specific OU, an additional groovy is needed for managed system policy map configuration.