I hope you're taking it easy. It's not just the surgery to recover from, but the initial illness as well. I'm glad you're getting back into your usual activities, though. How do you motivate yourself to walk? A dog, a friend, amazing willpower and dedication? I need external motivation.
I guess I made it a habit to do something ~30 minutes a day. It’s how I I try to start my day.
Oh! Have a look into something like The Conqueror Challenges! You put the distance you walk into the app and it shows you the distance you've covered and you unlock stuff about where you are virtually and you get an actual physical medal at the end.