Tell if hardwood floor is oiled or laquered
Oil has no body so the wood grain is just a tiny layer of oil away if you pick an area out of view when you scratch oil it actually will damage the wood, 

Lacquering or varnishes like varithane have body and a layer above the wood that can look like a magnifying glass to the grain and when scratched it usually turns color yellow / white this is the layer of “paint” to use your words. You may get a better idea by looking at photos online of oil finished verse varathane most times once you know it is easy to see.