In the Processing options section, in the Post processing activity field, enter the name of your post-processing activity. The post-processing activity can connect to any external entity to get additional data, and the activity can enrich the OperatorID page with attributes available on the assertion page
You can put debug on the activity pySAMLWebSSOAuthenticationActivity (logger:Rule_Obj_Activity.pySAMLWebSSOAuthenticationActivity.Code_Security.Action for pySAMLWebSSOAuthenticationActivity) and see the logs: verify the saml response attributes and see if they are mapped properly in authentication service mapping tab.
If you want to create operator, you have to make use of the model user located in the orgunit page.
For that you have to map the attribute values coming from IDP to pega properties.
Using OOTB activity pySAMLWebSSOAuthenticationActivity without customizing, you have to map IDP attribute values for pyorganization, pyOrgDivision, pyOrgUnit and pyUserIdentifier to create an operator in pega.
You can also use SAMLTRACER addin in Mozilla browser /samltracer in chrome to check the attributes which are coming from IDP.