How to remove steel wool scratches on a wood table top?

The previous owners of my home drywalled the basement bedroom and family room. They didn’t do it correctly and I can see each piece on the walls and ceilings. What can I do to repair this without having to tear it down and start over?

I am buying a home that has brown paneling interior doors. I can not afford to replace them with new doors. So I am thinking of painting them white. How do I go about doing this? What type of paint do I use?

I have a set of bunk beds that are real wood (medium brown color). I want them to be black. They were factory done – no DIY refinishing has been done on them before. They are stained now. Should I paint them black and if yes, how do I prep