How do I make the mouse icon change when it is hovering over a part?

You can use the Cursor’s .Target property to read the current BasePart the Cursor is hovering over. Using a conditional, we can compare the Objects to filter for one specific Instance.

Then, using .CursorIcon, we can change the Icon through a decal ID.

local Player = game:GetService("Players").LocalPlayer
local Cursor = Player:GetMouse()

local SetIcon = --// Id Here

local Part = workspace.Part

Cursor.Move:Connect(function()
    if (Cursor.Target == Part) then
      Cursor.CursorIcon = "rbxassetid://"..SetIcon
    end
end)

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