To be able to follow along in this tutorial, please use the positional information to access the proper Fermi-LAT photon data and Spacecraft file: https://fermi.gsfc.nasa.gov/cgi-bin/ssc/LAT/LATDataQuery.cgi
Make sure that you list your event files the proper way to be used in the configuration file.
This tutorial is based on the 10-year 4FGL Catalog (4FGL-DR2), or v27 of the catalog: https://fermi.gsfc.nasa.gov/ssc/data/access/lat/10yr_catalog/ This is because Fermipy currently cannot work on the latest DR3 catalog. Once it's updated, this tutorial will be updated.
Please also make sure that the galactif diffuse and isotropic diffuse files in place.