What does the following essay topic mean: "The waiting room of a railway station presents a wonderful opportunity to observe human behavior. Describe your experience in a waiting room"? How can I write one on this topic?

Are you asking for clarification on the essay topic?

Imagine you're waiting for a train to arrive and you notice other people near you. Maybe they're waiting for the same train as you, or maybe they're just waiting for a friend or somebody else to meet them there. 

While you're waiting, you can take notice on what people are doing near that station. One example can be the situation I just mentioned: Other people waiting for something next to the railway station.

There are many possibilities on what they're doing. And the experience of imagining those possibilities is how you perceive it to be.

I always get anxious in waiting rooms because people have
nothing better to do than stare at youI
hate when this happens because I get self conscious and start looking down like
a wussie. Am I over analysing this or what?

In a waiting room it is inevitable that you will be waiting
with complete strangers. If you have not been introduced or have nothing to
talk to these people about, then eye contact is going to be awkward.

You have 2 options, either look at the person or don't look at them. If you
stare at them, you will come off as some kind of weirdo. So the best option is
not to look at them. When I'm in a waiting room, i always get my phone out and
text people or play a game on it. If you have no phone, grab a magazine or just
fidget with anything you can find. Take your attention away from the urge to
look at people. Try not to sit directly facing people as this will make it
harder to avoid eye contact, either sit at an angle or take a seat where no-one
will be facing you. If you do make eye contact just be polite and smile then go
about your own business again. It does not mean you are a wussie because you
don't like making eye contact with strangers, its just awkward and by not
staring at people you are doing the best socially acceptable thing to do.