It depends on how much damage you did to your floor.
If you just badly scratched the surface, then a thorough cleaning followed by a light sanding for adhesion and two coats of Polyurethane will fix it. Try a small spot first to make sure you are not encasing your first mistake in plastic.
If the damage is more extensive, you will have to sand more. Unless you have to remove a lot of material, belt sanders and the circular floor sanders may be too much; they can actually grind down your floor.
Check with your paint store or home centre, I used a water-based polyurethane with great results. The floors were physically smooth, so I used an orbital sander with 100-grit paper and a hand sander on an extension, like the one they use to sand walls. That made white spots on the floor. Do not sand all the original finish off unless your paint specialist recommends that you do so, otherwise you will have to treat for bare wood first. Vacuum thoroughly and clean per finish directions. My floor was cleaned before sanding, so I used a damp rag to remove all the dust.
Apply the new finish with a paintbrush on the edges and with a special applicator for the floor. Apply only in the direction of the grain (parallel to the floor boards). Pay special attention at the transition points like doorways. If your floor runs parallel to the doorsill, finish at the line between two boards, if your floor runs perpendicular, feather in a straight line.
It’s actually quite easy.