I went to a paint store to get 2 separate gallons of paint. One was for my hardwood floor. The other was for the surrounding walls. It is a small room. The colors I chose was a latex flat White with a tint of pink (a blush) for the walls

I am going to paint 2 bay windows (exterior) overlooking the front of the house. The previous white coats are cracked and need to be sanded down somewhat. Do I have to prime them first? I am going to paint them white again.