Sounds like you have a mystery floor. It could be an old harder linoleum or some other type of floor.
Why do you want to fix the scratches and dents, it will only look repaired and stand out.
There are so many new products on the market , go check them out. New floating floors go right over the old ones with minimal preparation, and look great. If this is a kitchen or bath, try to stay away from carpet...yuck.
Go shopping and ask lots of questions.