Not everything on the internet is nonsense; some predictions are credible, even if they aren't 100% accurate. But as long as the prediction is even remotely close to the market price, it should be considered the best of the many predictions available online. Furthermore, we're not forced to believe other people's predictions; everyone can make their own predictions based on their own research and analysis before believing what others say on social media.
Not all predictions are nonsense, but most of them are. Most predictions are without research or analysis, it's all just people's hopes and even random guesses when asked by someone. Therefore, predictions are for entertainment purposes only, nothing more.
But yes, the best way is to do your own research and make your own predictions. Investing based on other people's predictions or advice is not a wise strategy.