To make sure that everything is legal, you need to make some prior checks.
You need to check each website’s ‘Terms of Service’ page – there you will find info about how much content they allow to be republished. Some will allow full content to be republished, and will require just a back link to the original article, while others will allow only a portion of the content to be republished. This should be visible in their ‘Terms of Service’ page.