10,000 steps a day (roughly 5 miles) is a lot, so kudos to you if you walk that much in a day
On average days, I walk roughly one mile (not including workouts). We went to the mall last weekend and walked about 6,000 steps (3 miles) in 3 hours
If I join your challenge, I would start low (2,000 steps/day or 10,000 steps/week) and gradually increase. You might get more replies if you post/ask in the Exercise
section. Good luck!