Why can't I do Table:GetChildren()?

I want to make a table:GetChildren(). The reason I'm doing this is because I want to save the data, so I make a table. But, turns out I cannot do Table:GetChildren(). This is my error:

ServerScriptService.DataStoreScript:20: attempt to call a nil value

Am I missing something? This is my script(Line 20-23):

                for _, v in ipairs(Table:GetChildren()) do
game.Lighting.Folder:FindFirstChild(v.Name):Clone().Parent = workspace.Folder
end