Hi Everett, 

Thank you for reaching out! I'm offering some suggestions for you below, prioritizing plants that tolerate full sun, are low-maintenance, bloom at different times from each other (so that you have blooms throughout the season) produce red or white flowers, and are native species (plants that are a part of/supportive of our local ecosystems): 

1. A really nice white flowering plant that could be great for you is moss phlox (phlox subulate). It's a lovely green ground cover and an early spring blooming plant. Its available in a number of colors, so you'll want to be sure to find it in white. It could be nice to plant a few of them along your wall or along the pathway. 
2. Foxglove beardtongue is another white flowering, sun loving flowering plant, and also has beautiful reddish purple foliage in the fall. 
3. Butterfly milkweed (asclepia tuberosa) is another vibrant and vivid sun-loving plant. It's a bit more on the orange side of red -- but offers some beautiful intrigue and is a gem for pollinators. 
4. If you'd like a shrub, black huckleberry is a great and nicely in the red family -- in the spring (April/May) it has dangling clusters of red flowers, and its leaves turn to a beautiful, vivid red in the autumn. 

If you'd like to keep pursuing options, take a look at this guide offered for free -- You can take a look at the column that states whether the plant likes sun or shade, and also take a look at the bloom color: https://mdflora.org/publications/gardenersguidelines/gguides.html

All my best, 

Rebecca