I don't understand when does the five year look back start. My parent is 83 and healthy

The five year look back begins on the date that the Medicaid application is made.  At that point, the intake worker looks back through five years of financial history to see if there were any transfers made, and if there were, the transfer make the applicant ineligible for Medicaid.  The other way to look at it is if you made a transfer today, and then five years form now made a Medicaid application, the transfer would be beyond the five year look back period.