Content in online courses should always be ethically sourced and attributed to the copyright holder. Moodle gives you an easy way to set the default copyright licensing to be used on content that you add to your courses.
In the Moodle File Picker, when you upload a file from a repository or your computer, one of the properties you can set is the License, as shown here:
Licenses you can select from for each file you upload: (Links to definitions for each license type)
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