There are plenty of free or paid resources on the web for tracking duplicate content.
What I generally use as an easy solution is the plagiarism checker provided from SmallSeoTools. Which is free and simple to use (not very advanced though). You can also produce similar results by searching on Google for random sentences throughout your text to see if they have been copied anywhere else.
There are more advanced paid solutions to finding plagiarism, which is used by academics, but for the average website, a free online checker would do fine.
Also, if you want to constantly track and be notified whenever your content has been copied, you can sign up for a notification service like Plagiarism Checker
Daniel Rika - Dalerio Consulting
https://dalerioconsulting.com/
info@dalerioconsulting.com