Vector3Extensions.cs

public static class Vector3Extensions
{
    public static Vector3 GetPointOnSphereAngle(this Vector3 center, Vector3 targetDirection, float angle, float radius)
    {
        float angleInRad = Random.Range(0.0f, angle) * Mathf.Deg2Rad;
        
        Quaternion dir = Quaternion.LookRotation(targetDirection - center);
        Vector2 pointOnCircle = (Random.onUnitSphere) * Mathf.Sin(angleInRad);
        Vector3 pointOnSphere = dir * (new Vector3(pointOnCircle.x, pointOnCircle.y, Mathf.Cos(angleInRad))) + center;
        Vector3 distFromCenter = (pointOnSphere - center) * radius;
        
        return pointOnSphere + distFromCenter;
    }
}