There are many books available through the U-M Library to help you learn GIS, including an increasing number of ebooks that can be accessed from any location.
Items can be found via U-M Library Catalog Seach, and a few searches to get you started are:
A search for GIS in all fields, sorted by year with newest items at the top.
A search for "geographic information systems", sorted by year with newest items at the top.
ESRI Press, 2017. Gina Clemmer.
Inspired by a poll of 500 GIS practitioners, The GIS 20: Essential Skills is an easy-to-understand guide that emphasizes 20 skills most people need to master to be successful using GIS. A quick and comprehensive introduction to GIS fundamentals, this book includes a data CD for completing the exercises. Written for professionals with no time for classroom training, The GIS 20 can be used for independent study, or an as-needed reference.