Drag the steps to configure a Cisco ISE node as a primary administration node from...

https://www.cisco.com/c/en/us/td/docs/security/ise/2-4/admin_guide/b_ise_admin_guide_24/b_ise_admin_guide_24_new_chapter_011.html

Step 1

Choose Administration > System > Deployment.

The Register button will be disabled initially. To enable this button, you must configure a Primary PAN.

Step 2

Check the check box next to the current node, and click Edit.

Step 3

Click Make Primary to configure your Primary PAN.

Step 4

Enter data on the General Settings tab.

Step 5

Click Save to save the node configuration.