Copyright
Copyright is someone's right to his or her own work and can decide whether or not to let someone else (other than the creator) use it and how they can use it.
Fair Use
Fair use is a law that allows, under certain circumstances, some people to use copyrighted material without having any copyright form.
https://www.teachingcopyright.org/handout/fair-use-faq.html
Listed above are some webistes that can help you better understand copyright and fair use.