How many sunrises and sunsets would you see if you were to spend one year on Mercury?

The Mercurian year only lasts HALF a Mercurian day.

So, this this is an absurd question - it's like asking how many sunrises and sunsets there are on Earth during half a day here...

A Mercurian day lasts 176 Earth days (a day on Mercury lasts twice as long as its year due to the 3:2 resonance, i.e. it rotates 3 times around its axis while it moves exactly twice around the Sun).

There can be 0, 1, or 2 sunsets and sunrises on Mercury during the same Mercurian DAY - it all depends where you're standing on the planet.

At the poles the Sun always remains partly over the horizon, caused by Mercury's axis being perpendicular to its orbit. So, 0 sunrises or sunsets here.

2 sunrises and 2 sunsets can only be seen when you're standing near 90° western or eastern longitude : longitude 0° on Mercury is the meridian where the Sun passes overhead during the perihelion passage for an observer standing on its equator. Most of the day the Sun moves east to west, but from 4.25 days before until the same time after perihelion passage, the Sun slowly moves west to east in the sky. 2 rises and sets can then be seen in spots where this back and forward movement happens on the horizon, which is around 90° east and west (for any latitude except near the poles).

Near the poles 2 sunrises/sunsets can happen at any meridian - except near and at 90°.