Look for studies that are peer reviewed. Credible news sources will state whether the studies are peer reviewed or not. Though if they say it was published in a well-known scientific/medical journal (e.g. JAMA, The Lancet), then that can be assumed. Findings in peer-reviewed journals are "real" and they will state the limitations of the findings which will tell you their level of completeness.

If you're only hearing anecdotal stories of adverse reactions and not seeing the full, contextual data, then change your news sources. Just the other day I saw that after the first 13.8 million doses administered there were only a bit less than 7000 adverse events, 91% of which were deemed minor. There were ~122 deaths among the people who got the vaccine and none of them were attributed to the vaccination. [I'm doing that from memory - can't find the source at the moment, but I'm pretty sure I'm close to the actual numbers.]

So how do I know if I'll be one of the small number of people who die? I don't. But I trust the statistics that my chance of having problems is FAR smaller with the vaccine than without. That's sorta the whole point of vaccines. Science is a wonderful thing.