how do i make a save function where the thing i need to save is whether a part is black or red?

You can use DataStores.

Steps:

• Define the datastore with the GetDataStore function of DataStoreService

• Save to the datastore using SetAsync ~ provide a key to retrieve the value, and the value to save.

• Load from the datastore using GetAsync ~ provide the key that holds the desired value

--Define datastore
local ds = game:GetService("DataStoreService"):GetDataStore("Part")

--Save to datastore
ds:SetAsync("Color",workspace.Part.BrickColor)

--Load from datastore later using
ds:GetAsync("Color");