Question

If the ball was thrown with an initial velocity of 20m/s and an initial velocity horizontal velocity of 30m/s.what will be the total time of the flight of the ball? consider that the ball was released from the ground and landed some meters away.

Answer 1

I assume you meant an initial vertical velocity of 20 m/s. The horizontal velocity does not matter.
Since v = 30-9.81t
v=0 at t=3.06 seconds.
That is when it has reached the top of its arc.
So total flight time is twice that.