While scripting, i have came across "trying to index number with "Touched""

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4

Try

for _, fadingParts in pairs(FadingPartsFolder:GetChildren()) do
	fadingParts.Touched:Connect(fade)
end

You used fadingParts like it was a number, since for uses i and v (i,v)
For example,

for i,v ..

You used it like:

for fadingParts,v

And I recommend you to not use ipairs, use pairs