Create a user OTRS with a federation with Windows Active directory.
First, you haft to check Active Directory if the user is a member of the correct groups.
After picked correct groups you go to OTRS then
fill in what is necessary for the form
The rest of the form for creating an agent can be the default
Then you go back to and pick
Look for the user you have created and click on him, pick what roles the user should have.