Which is the North Star?

It's the one named "Gou Chen" in the picture.

There is the Big Dipper on the left, like a big spoon. The distance from the bottom "spoon edge" to the "spoon mouth" direction (the right side of the figure) is about 5 times, which is the Polaris.

Polaris refers to the star closest to the north celestial pole. Its constellation is called Ursa minor, and its official name is "Alpha Ursa minor". It is the brightest star in Ursa minor. It is a yellow giant with a spectral type of F, about 434 light years away from the Earth, with a mass about four times that of the sun and an apparent magnitude of 1.97.

Although it is not very bright, there is no brighter star nearby. This star was called "Gouchenyi" in ancient China.