Projectile shooting with range, height & flight time to display in UI

I am creating this game by using Leap motion controller, my right hand is Cannon, it shoots cannonballs when the gesture is recognized. Speed of the ball is cannon shots speed & Force on impact is the force calculated on impact which is all working fine but when I am trying to get the correct values of projectile motion such as Range, Height of projectile and Flight duration my logic seems to vanish. I am pretty sure my logic is wrong. I am a beginner in game development. Below is code I am using:

 public float gravity = 9.98f;
     public Transform firingCannon;
     public Text flightTime;
     public Text projectileSpeed;
     public Text projectileDistance;
     public Text RangeofProjectile;
 
     public Transform MyPosition;
     private Transform myTransform;
     public Transform Target;
 
 void Start()
     {
         StartCoroutine(CalcSpeed());
         StartCoroutine(CalcFlightTime());
     }
 
 private IEnumerator CalcFlightTime()
     {
         bool isPlaying = true;
         while (isPlaying)
         {
             Vector3 prevPos = transform.position;
             yield return new WaitForFixedUpdate();
 
             float ProjectileVelocity = Mathf.RoundToInt((Vector3.Distance(transform.position, prevPos) / Time.fixedDeltaTime) / (Mathf.Sin(2 * firingCannon.eulerAngles.z * Mathf.Deg2Rad) / gravity));
 
             projectileSpeed.text = "Projectile Range: " + ProjectileVelocity + " m";
 
             float Vx = Mathf.Sqrt(ProjectileVelocity) * Mathf.Cos(firingCannon.eulerAngles.z * Mathf.Deg2Rad);
             float Vy = Mathf.Sqrt(ProjectileVelocity) * Mathf.Sin(firingCannon.eulerAngles.z * Mathf.Deg2Rad);
             //projectileSpeed.text = "Velocity of Projectile: " + ProjectileVelocity + " m/s";
 
             float velocity = Mathf.Sqrt(Vx * Vx + Vy * Vy);
             // Calculate flight time.
             float flightDuration = Vector3.Distance(transform.position, prevPos) / Vx;
 
 
             projectileDistance.text = "Projectile Duration: " + Vx + " m";
 
             //float elapse_time = 0;
             float TotalflightTime = 2 * Vy / gravity;
             flightTime.text = "Total Flight Duration: " + Vy + " s";
 
             float Range = velocity * Mathf.Sin(firingCannon.eulerAngles.z * firingCannon.eulerAngles.z);
             RangeofProjectile.text = "Range: " + Range + " m";
 }