Critical thinking is to analyze and evaluate a problem to form a judgement. You have to dig deeper and make a decision that is informed by evidence. You use critical thinking to spot fake news because if you didn't you would think everything was real. The steps you take to find fake news uses critical thinking. If you're looking at a news story you use the critical thinking steps.
1. Ask questions- Is this too good to be true? Is this a reliable source? Is this possible? How could this be true/fake? Who's the author?
2. Gather info- read past the headline, ask an expert.
3. Apply info- Is the concept logical?
4. Look at other points of view- Check other reliable sources (snopes/tineye) Don't be bias.
If you look at the author you wouldn't just think they're real you would have to dig deeper and search them up to make sure they're reliable. If you look at the URL and it has .co then that's a good sign that it's fake.