Yellow light on dashboard that looks like a submarine or fish is on. Should I be worried

That is an engine symbol. Read your owners manual for the meaning.

Could be anything from a loose gas cap to bad gas however the 2012 equinox had a power train issue might still be warranted

The gas cap is a good place to start. Have you gotten gas recently?

That's a Check Engine Light. Take it to an Auto Zone or O'Reillys - they will hook up an OBD II scan tool and read the trouble codes stored in your car's computer. No charge!

Means you're within range of a radio station playing a certain Beatles tune.

Perhaps the periscope has an issue.

The light actually is warning you to roll up all the windows as the car is nearing the water.