See these previous RG discussions

https://www.researchgate.net/post/How_to_check_the_plagiarism_of_paper_for_free

https://www.researchgate.net/post/Can_anybody_provide_plagiarism_checking_modules

http://en.writecheck.com/

You can create your account then select which package you need.

Hello. The first thing is to establish that there is no software that checks, checks or verifies plagiarism. These softwares what they do is find matching texts in the network or match the data with existing ones. After this verification process will give you a percentage of how coincident it is. Then it will be necessary to review and verify coincidence by coincidence to see what it is about.

The best-known softwares are:

Crosscheck, Turnitin, Ithenticate, Copyleaks.

Regards!