Different rinks can have different etiquette; "read the rink" before stepping into it.
I haven't been to every rink but there are some general guidelines you can follow to have the best experience for yourself and others. These rules are thrown out of the window at adult nights or some parties since the expectations of the crowd may be radically different. But I'm fairly confident these will age well.
Skating faster is way more enjoyable when the track is larger; faster skaters will tend to occupy the outer rings of the track. Slipperier wheels will have larger turning radii so that's another factor.
The middle is relatively still, and as the rings get larger, expect the speed to increase.
But what about the bars? I hear someone ask, I want to hold onto the wall. Most of us believe that newer skaters will be in fewer people's way if they are moving slowly closer to the middle area than on the outer rink. Since we don't want to encounter slower people on the outside, we will avoid slower people making their way to the middle. It's better economics for the whole rink.
The skater that is in front is not responsible for the skater behind them.
The exception is when the skater is doing techniques that takes up horizontal space–e.g., kicks to the side– the skater doing the moves should check behind and to their sides (like a driver checking their side & rear-view-mirrors).
Try not to completely stop; everyone expects others to continue skating in some direction. Breaking that expectation invites danger/risk.
If/when you fall:
If you are fine, get up and go! Please don't have an entire picnic on the rink floor
Hands off the floor so people don't roll over your fingers.
If/when someone falls:
Quickly evaluate, do I need to change my direction to give them space
Is the person likely to be seriously injured and am I truly capable of providing the best help?
Rinks tend to have skaters going in one direction, usually counterclockwise (CCW). Go that way! Just like driving a car, it's pretty dangerous to go against the flow of traffic.
There are slight exceptions when the rink is used for artistic skating, full-rink games, and sometimes during adult nights.