In my book I am adding some pictures, one of a wooden outside door set in a brick wall, the other picture is of a old house that is owned by the National Trust. Both pictures do not say they are copy write but can I use them?
By default, no, you cannot. Things posted on the internet might be free to see, but they are not free to use. You need to contact the author and get their permission first, and they might want to be paid for it. There are photo banks on the internet with pictures you might use for free, look them up. But even with those, check the licences to see what kind of use they allow.
Google and Bing have image search options for pictures you can use freely without asking for permission.
Permission needed or not, it's one thing to upload an image, it's quite another to put it in a published work. You want more assurance the image is useable than just it saying so on Google or Bing. Someone could have stolen the image initially. Bottom line, there are hundreds of thousands of images one can indeed use, but you want some legal trail to assure you can use the image before using it in a publication.
