How do you get rid of small dents and paint bubbles from previous painting before painting the old wall?

House exterior is light grey, shutters and decks are colonial blue. What color should the solid back door be?

We have almost finished a huge rennovation. We hired a contractor who hired a painting crew and they painted all the trim, windows and doors latex over oil. Now, all you have to do is run your fingernail on it and you can make it chip. Also put blue tape

I thought I would surprise my other half and finish painting the walls in bathroom. I have a few runs and his wall shines more than mine??