An hour is only 5k, maybe 6k steps for me (I'm sure it varies by individual). 12k is two hours of walking minimum, six or seven miles, which is a pretty big chunk - I did that much in college walking to class, and when I briefly lived in a city, but no way I'm getting that in on a daily basis out here in the suburbs.
I'm pretty sure steps count when you get up and go to the toilet...
When I did my masters, we were in a Chemistry wet lab 8 hours a day and during the first month I would come home completely exhausted. I realised later that this was because I wasn't used to being on my feet all day walking around even though it didn't feel like I was being active shuffling from machine to machine, fume hood to sink etc
So much depends if you work remote or not. Before covid, I would hit 10k steps with just a 30 minute walk after work because the office involved so many cumulative steps.
Since going remote, it is very difficult with a 60 minute walk. Walking 90 minutes after work is not going to happen so I just focus on my nutrition all the more now.
I work remote and live in a very car-centric suburb. I still somehow average about 10k steps a day with just daily chores and errands.
Maybe I should thank my parents for raising me the way they did because there's zero effort on my end other than the desire to take breaks outdoors, keep things clean indoors, and eat well. On that last point I try to cook most of my meals with fresh ingredients and enjoy shopping in person instead of delivery or pick up.
The other stuff, yeah no problem.