Appearing of a UI

How can I make the UI visible with executing the ability. I use UI.visibility(ForseOn). UI doesn't appear but there are no errors.

You can use the code below to enable the visibility of a UI object with the casting of an ability. This code requires two custom properties:

"UI": A core object reference to your UI object
"UIAbility": a core object reference to the ability object you will use to make the UI visibile

--A core object reference your UI object
local UI = script:GetCustomProperty("UI"):WaitForObject()
--A core object reference to an ability object that you will use enable the UI
local UIAbility = script:GetCustomProperty("UIAbility"):WaitForObject()
--function that will be called when the ability is cast
function OnCast(ability)
    --Force the "UI" to become visibile
    UI.visibility = Visibility.FORCE_ON
--Connect the "OnCast" function to the "castEvent" of the "UIAbility"

local uiTask = script:GetChildren()
local abilyty=script.parent
function qwe()
uiTask.visibility = Visibility.FORCE_ON


Would't it work like this?

Help me please!!!

I can"t understand this, Why can't I call an object by name or by identifier?

You can access an object by its name or ID using

--Get a Core Object based on its name
local object = World.FindObjectByName("Name of the object")
--Get a Core Object based on its ID
local object = World.FindObjectById("Id of object")

However, you will then need to keep a strict naming system for all objects. Using core object reference custom properties instead allows you to drag and drop objects and change their names without issues:

I would suggest watching this video:
Core Object Custom Properties