ISE relies heavily on "flows." You need to see how a user connects, how ISE queries Active Directory, how the policy set is evaluated, and how the result is pushed to the switch. Video training allows you to trace these steps visually.
YouTube is a treasure trove for specific "how-to" scenarios. While it may lack a structured curriculum, it is unmatched for solving immediate problems. cisco ise training videos
Any video that uses a VM with only 4GB of RAM. ISE requires 16GB+ to function. If their lab is slow, their teaching is probably wrong. ISE relies heavily on "flows