With all the accusations of "junk science" and "fake news" today, it's important to fact check scientific claims. Here are some good places to start:
Duke University's Reporter's Lab keeps track of fact-checking websites worldwide:
And these fact-checking sites often cover junk science claims and pseudoscience:
At present the most hotly-contended areas of science are around climate change and health (especially COVID-19, where the UN declared that the "epidemic of disinformation" is as deadly as the disease). These sites can help sort out what's true, false, and unknown yet.
Over time, peer review practices evolved to verify scientific claims made in traditional sources (some books, some journal articles). But almost none of the internet-only sources do this reliably!
So -- if your information comes from an online source, don't trust it until you've checked it. This guide has information about peer review, and more detail on evaluating scientific information both online and in print. For a quick check, though, the "Trust It or Trash It?" Quality Assessment Toolbox (link below) is a great start.