So I recently bought a piece of furniture which (based on my research) has a polyurethane finish. After it arrived I discovered it had scratches, which I believe is polyurethane flaking off (you can flake it off/scratch it with your fingernail really easily). They are only surface scratches and don't go into the wood however.
How would I go about removing the surface scratches? I've seen articles suggest either sanding the entire polyurethane finish and applying another coat or sanding, applying a finishing wax and using 0000 steel wool to polish.
I know nothing about woodworking and I'm not sure what article to believe so was hoping to get some helpful advice.