Enlarging Photo Text

I am trying to add a text area to a page in my book. I am using Lightroom Classic CC 7.5. I couldn't figure out how to add a text to a custom page so I decided to try and enlarge the photo text area. Now that I have the information typed in the area continues to be gray wanting a picture to be added. I am wondering if this will continue to be gray in printing or will it be black like my background? Also is there anyway to make sure the photo boxes are lined up when you custom a layout?