Is this windowsill ruined? (Pics)

[DeeEyeWhyBecauseIGotta]

I’ve stripped the white paint off this windowsill as I’d rather have natural/varnished wood. However it has revealed some staining on the wood. Do you think it’s salvageable? I’ve scraped off a few layers of wood with the stripping process so I think it goes quite deep. I’ll sand it of course but I don’t hold out much hope. So I guess I’m wondering whether there’s another way of fixing this?

Have you tried using an electric sander?

Not yet but I have a mouse sander I’m going to try. But I’m expecting this to go quite deep. My dad has a more professional sander I could try. Hoping it’s that straightforward as I’d rather not paint this white again.

Wood does not need to look perfect. Coat it with varnish and forget all about it.

If it is a water stain it can be removed using oxalic acid. Barkeepers friend powder contains oxalic acid. You can google how to remove but basically mix it to a thick paste and spread on stain, leave until paste is dry then rinse off to stop bleaching process and dry the wood with rags. Process can be repeated to remove remaining staining. Finally sand and stain/varnish with a waterproofing product. (edited to remove typo)

Use oxalic acid on the wood.
Sand using 120 grit then paint the stain with oxalic and then apply it to the whole windowsill. Wait 20 minutes or so then rinse it off with water. You might have to do it a couple of times but the stains will go.
Once it is dry, sand with a fine grit then coat it with Osmo oil or boiled linseed oil and it will look good.

Thank you so much for that advice! I have some barkeepers friend powder so I can get on that tomorrow, brilliant! Thank you

Yeah I’d agree with this.

Sand it really well with increasing finer grit rating paper, varnish, it’ll look fine.

Ok that’s a good point. There’s more staining like this at the other end so at least its balanced 😬😂

This worked like a charm! Thank you so much ! ☺️