Grammarly is a great tool to help you avoid plagiarism as AbieAJ has written below. I use it to and I can´t live without it as it is phenomenal in helping you with spellchecking, grammar in addition to plagiarism.

It helps that you can become an affiliate of Grammarly as well :-).

When it comes to the question to site resources, get into the habit of referring to the resources you have been using for your content consistently from the beginning.
That will help you to stay out of trouble. And always try to rewrite the info from the resources and convey that info to your audience how you have understood it.

Roy

Hi there are tools you can use. We use Grammarly dot com premium version of which checks for plagiarism.