u/Defiant_Amphibian_72

I found this on the side of the road. It’s part of a bench. These are holes where the previous owner tried to screw the slate from the top. How can I remove what’s in the holes and fill them so it looks nicer. I’ve been a fair bit of beginner woodwork (small furniture) but I’ve never work with wood this nice, dont want to screw it up. The idea is to use it for a bench or table.