We have a rescue dog and she is 8 years old. We have had her two years and she is a sweetheart. She loves to lay in front of the big picture window in front where she can look out. We are moving and there is no place where she can do this in the new house. What can we build or fix for her so she can see out a window?

Is there any window that would work for her as to a good size and things to see outside, like the back yard activities? I bought a carpeted step stool for my elderly cat to get up into one of our lower windows that we widened the bottom of and added a section of unused carpet so he could sit in the sun and watch the squirrels. Pet Stairs

I have my couch arm right next to a big bay window right at the level of the ledge and both my dog and cat love it.
You could also use boxes or milk crates as steps up to a small table or big crate that has a pad on it, just below a window. Even a dog crate would work and serve two purposes.
If you can afford to replace a solid door with a glass one, they love that too.