I had this old wooden top off an old portable dishwasher. They don't make them from solid wood anymore!!
It had some deep cuts and stains.
I used a scraper to take a small layer off the top. It had a coating on it that would bind up the sander.
I used various grits of sand paper. Started with 80, 100, 150, and then 220 to finish it.
Take your time so that you get all the scratches out.
Once you are happy with the way it looks, wipe it clean. Some stains were a little deeper than I thought. I was happy with the look.
I use Tung Oil for a coating. It's safe for food contact.
Just pour a little in the center and start spreading it all over. I used a lint free rag to spread oil. Dispose the rags in a safe manner, it could start a fire if disposed incorrectly.
Let the first coat dry before applying second coat and so on. The more the usage (of the item you are coating) more coats needed. I'll probably do about six coats.
Once it's dry, start using it!!