There are hundreds of tutorials on the Internet for all different levels and topics of GIS needs. This guide suggests a number of GIS tutorials for various topics and software. Coursera offers several courses of note.
UH students, faculty, and researchers have unlimited access to Esri's self-paced e-learning catalog — online videos, training materials, and study plans. If you are new to ArcGIS, we highly recommend starting with some of the basic tutorials that introduce the ArcGIS line of products:
There are many online classes on a wide range of topics that are free to UH Manoa students, faculty and staff.