If your use of a copyrighted work falls outside the limits of Fair Use or other copyright exemptions for educational use, you should obtain permission, meaning a license, from the copyright holder for use. The license will cover the specific amount that can be copied and the ways in which the work can be used.
The Copyright Act of 1976 grants a number of exclusive rights to copyright holders, including:
Without one of the legal exemptions to copyright, It is illegal to violate any of these rights held by copyright owners without first obtaining permission from the copyright owner.
See Getting Permission from University of Texas Libraries' Copyright Crash Course by Georgia K. Harper.