I assume you are referring to protecting the texts of a website from being copied by visitors? There are various techniques for this, but all of them can be circumvented. What is published on the internet is also accessible and copyable by everyone.
Nevertheless, you can of course build in a hurdle to make that more difficult. For example, there is this plugin:
https://www.ads-software.com/plugins/wp-content-copy-protector/
Finally, however, here again the warning that the protection is only a hurdle and can easily be circumvented.
