The chances of an asteroid from the asteroid belt hitting Earth are very close to zero. The chances of a so-called "near Earth asteroid" hitting Earth are much higher... in fact, they hit Earth all the time, and are seen as meteors ("shooting stars").
It is outside of the asteroid belt. That is to say it's not within the belt. However, sometimes we say the Earth is located "inside" the asteroid belt. By this we mean Earth is between the Sun and the asteroid belt.