I'm not a pro at wood refinishing, but given its current state, it shouldn't hurt to give it a light sanding, stain and coat with polyurethane. Shouldn't be too hard. I'd just go easy on the sanding and take your time with medium grit and move to fine grit to get it nice and smooth. Polyurethane products should have directions on the can - usually a light fine grit sanding between coats. Some stains also come combined with poly to save time.