The plants you choose will depend on what kind of sun you get, I see lots of trees, so assuming shady most of the day? What direction does the house face, north, south? Do you get lots of rain in your area, and if so does the soil in the beds drain well? Where does the rain gutters drain? they may need re-routed to avoid washing out plants. Do you want mostly greenery, lots of color, plants that are useful-like herbs, fruits, ect or just for looks? Do you want plants that you don't have to do much work-pruning, dividing, ect. You need to decide some idea of what you want. Typically shade areas will get hostas, herns, hellebores, mosses, nandinas, woodland phlox, hydrangeas (part sun) ect. Best to drive around the area and see what is doing well for others around there.