Funnily enough I've lived in all 3 categories of these places.

Rural: no sidewalks and large distances. Walking is usually impractical because of distances and lack of sidewalks. Your house is most likely right on the side of the local road. To get anywhere your real option is biking, but cars go fast on these road. You better not be caught at night or on heavy rain, because some grandma is going to take you out. Many times people were shouting at me from cars passing by, one time threw an empty can, couple times some wrappers and stuff.

Suburban: walking most likely is an option as is biking. If you are lucky, there are sidewalks, but I'm my case there were large portions of the road without sidewalks. Even worse sometimes short route takes you through intersections that aren't easily navigable by pedestrians. No lights, slip lanes etc. it's very uncomfortable walking or biking on such roads for long time. Your best option is to try to find circuitous route through neighborhoods and only cross major roads when needed. That increases travel time by a lot at expense of higher safety and keeping your hearing. Fewer shouts from the car, but they happen still.

Urban: that's the most walkable setup. The only one I really recommend. I've lived in what considered a very bad part of town and managed to walk to store and gym with no problem. But I'm a guy and was young then, so your milage might vary.