Is the direction of average velocity same as the direction of the instantaneous velocity in projectile?

No because the tangent varies in a curve on a graph.Average velocity just gives u overall motion and direction. But to find the direction at that point, average velocity doesn't help. Got it!

No.

Average velocity is total displacement/time.

So if you throw a ball and after 10s it lands 20m to your right, the average velocity is

20m/10s = 2m/s to the right.

But the instantaneous velocity continuously changes through the flight. When you throw it, the instantaneous velocity when it leaves you hand is several m/s at some angle to the horizontal.. The magnitude and direction of the instantaneous velocity change from moment-to-moment during the flight; as the height increases the speed decreases and vice versa.

If you're traveling at a constant velocity, the average velocity is the same as the instantaneous velocity at any point.

no ..

average velocity is total displacement by total time taken ( it is constant for a given situation) .... where as the instantaneous velocity changes at every pt.

No