Hi Bob - You should say, at OUR age.

You want to add the porch to the home that is missing a porch, is this correct.

Select the photo, then switch to the Shape Tool.

You should see four small squares on the for corners of the photo. Drag a selection rectangle (with the Shape Tool) around the two top corner squares (they should become red outlined squares) and use your down arrow key to lower the top edge as desired. Repeat this for the other three sides until you have just the porch left.

Now you can add the porch to the house that is porch challenged and if the perspective and angle are correct it should look like it belongs there.