Yep, as already said start of slow and steady. I probably run more than I cycle these days but when I started out running (maybe 5 years ago) I completely killed myself on the first few attempts. Your cycling fitness is not your friend here as it’ll allow you to go much harder than you should at the start. Feels ok at the time but you’ll be limping for days.
Start out with a 10 – 15 minute run. If you feel ok the next day then up it a bit. Once you can handle 30 minutes you should be able to survive a 10k alright. Even at a very gentle job it shouldn’t take more than an hour.