War Thunder is a game about war. In War Thunder you can to choose to become a tank or a plane.
Tanks are the easiest to use as you have aim assist and a x-ray to see where you are aiming inside the tank.
When aiming inside the tank you have to try to eliminate the crew for it to count as a elimination. As for planes there is no aim assist and you have to take down opponents with no help.
But there is a crosshair in the middle of your screen to help you aim.
There is also a little circle infront of planes that you have to aim and fire at to hit they plane because the bullets need time to travel to the enemy plane.