Creative Commons licenses are developed to make it easy for readers and users of your work to understand what you allow them to do with your work. Creative Commons is a part of the Open Science movement. On this webpage you can read about Creative Commons licenses, copyright, Plan S and you can select a Creative Commons license for your work. Specifically, using a Creative Commons license gives users information on how to reuse your work in an Open Access context.
You can also find more information: Open Access