I started out doing distance, because that's what I've always done in the past, but I've started not worrying about that for now. Before I got pregnant I was walking 5 times a week, 6 miles two days & 2 miles 3 days. But I'm not up to that yet; I can barely do a mile right now. So I just quit worrying about distance until I feel a lot better. I was just feeling bad for not being able to go as far.
Do what you can. Walk til you feel yourself getting tired, or until your back starts hurting (if you're like me), then sit & rest for a while, turn around, and go back. When I was in Virginia, I'd walk to a certain little area of shops, have lunch or at least something to drink, then walk home.
Find a way to do it that makes you happy. Lately I've been doing laps around a sort of nature trail on the Air Force base here, which I enjoy because I never encounter anyone else there and I get to watch the ocean and see the planes coming in to land.
I had a treadmill until we moved here, but honestly I hated it. I was always chasing the wall, & I never caught it.
But some women love treadmills. So it's definitely a matter of finding out what works for you.