Please know that there are no age limitations or requirements. In fact, there are no rules. There is etiquette and common sense. But, if you are in reasonably good health and can walk, even with a cane, you should find a way to accomplish a Camino.
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Many of us, veteran pilgrims are well into our sixties and beyond. Certainly many more are younger than this. I completed my first Camino in 2013 on my 60th birthday at the Cathedral in Santiago. But, whilst on Camino it is not at all rare to meet pilgrims who are in their 80s, even walking solo.
Also, pilgrims with physical limitations abound. Sight challenged persons either walk very near to or tethered using a dog walking sort of arrangement to a sighted person.
Last summer, a youngish British fellow with MS walked using full-arm crutches from St. Jean Pied de Port all the way to Sanitago de Compostela, unassisted, and carrying his own rucksack.
Weekly, pilgrims in athletic wheelchairs end up at the Pilgrim Office to claim their Compostelas. Some, but not all, are accompanied by able-bodied friends or relatives.
I even met, in two successive years, a pilgrim who, in 2010, had suffered a stroke affecting his entire right side. His therapy, after three years, advanced him to be able to walk by taking a step with his good leg and sort of half-dragging his "numb" leg along, at a half-a-meter-per-step pace. Using a single walking staff in his affected hand, he walked from Strasburg, France to St, Jean Pied de Port, rested up for a week or so, then continued on to Santiago, again, on his own. He did this both in 2013 and 2014 that I personally know of. I did not happen upon him in 2015 or 2016, but we were likely at Santiago during different months.
Diabetics find ways and means to maintain their insulin insulated and cold enough. Apnea sufferers tote their CPAP machines with them. Anything is possible if you set your mind to it, and just ask for help. One of the basic "rules" along the Camino is that "the Camino provides..." Try it, and you will see what we mean.
My point in all this is that, regardless of age, and almost regardless of physical limitations or health conditions, where there is a will, a way can be found.
BTW, "that movie" made the Camino look a bit easier than it is. Certain "literary and cinematic license" was taken during the filming of the movie to enhance and preserve the plot . While is is not quite a walk in the park, it is not overly-difficult. You just need to remain flexible, and modify your expectations.
I hope this helps, and we see you out there.