There are several ways to find out fake news, one of them is looking for the most trusted news in the Internet and search from different source, from the forum and people's testimonial also can be one of way, fake news could be dangerous for the market, it could divert the investors into the wrong direction
This is correct, you always have to check the source of the news, some are for people to be scared and have to sell their bitcoins quickly and cheaply, the market not only has traps in their operations, but externally move all this News type and so you can influence the price.
The major problem now is how do we know the real news and even real a source? going by the numbers of cryptos news blogs, news media etc flooding around the world, I am well informed that news have impact and influence price, some news create FUD thus sending fears to newbies who wouldn't waste any time but start dumping out-rightly thus crashing the price while a upcoming positive news attract investors who invest and invariably pump the price.