That’s a very subjective question and the answer therefore will not be objective either.
Do you hike regularly back home? Did you ever do multiple-day hikes? The Camino will be absolutely no problem. Remember however, that walking 3 or 4 days in a row is not the same as walking a month in a row.
Never hiked before? You should train at least a little bit at home until you are comfortable with walking at least 15 to 20 km in a day.
Will it be a major problem if I can’t walk 15 km per day? No, you will simply need more time to complete a certain distance, that’s all.
We started our Camino experience with the Camino Portugues. We only walked 5 or 6 km the first day. At a certain point we were doing 15 km per day and we decided that, to keep things relaxed and be able to enjoy the local food and local culture with plenty of time, we would never walk more than 15 km on average.
Is it wise to be able to do a bit more in case of emergency? Yes. If you can’t find any accommodation after walking 15 km, it’s very nice to be able walk an additional 5 km without pain in your feet. Having said that, it’s just a matter of planning…
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