What kind of technology was used during WWII?

As for guns, the standard rifles were either bolt action, (i.e. Springfield) or semi-automatic (i.e. M1 Garand). There were also some submachine guns and machine guns to.

1. How did it evolve during the war?

There were new guns going into development.

The communication was greatly improved on the battle field.

The planes were much more reliable and had more fire-power.

Submarines came into play and were actually effective.