When a body is moving in a circular motion the acceleration keeps changing, will it be zero when it comes back to the same point it started from(will the average acceleration be 0?)
Acceleration is a vector quantity, meaning it operates both in the form of magnitude change and direction change. If the velocity of a body is continuously changing in magnitude or direction, it's said to be accelerating. In a circular motion scenario, the velocity might be both changing in magnitude (as in angular acceleration $\alpha$) or in direction (as in centripetal acceleration $a$ pointing towards the center). To to answer the question, a body still in a circular motion is always accelerating direction-wise.