In total, I cycled over 2,000km from Lisbon - Santiago - Pamplona - Bordeaux - Paris - Dieppe, then ferry to UK. Most I have cycled in my life is 90km over two days, about a year ago. not bad for a 72yo. Before starting, I did not believe I would reach Santiago, but it was not that difficult. Just paced myself. Including days off, averaged 50km a day. Hostels in Portugal and Spain. France was a financial shock. Bought a tent and sleeping bag at Decathlon, and all was good after that.
French campgrounds were about 20 euro, but came with showers and often a cafe. People I met in France were friendly and helpful. The couple of times I had a puncture a few people stopped to help. People in Spain and Portugal were friendly as well. Big problem in France is lack of , about 50 km to 60 km between cafes or supermarkets. This needs careful planning as a few days I did not eat. Finding a supermarket/cafe needs to be an important part of each day's plan. Cafe food is usually good, but supermarket food is cheap and good. Overall, I prefered cycling in Spain, France was a close second, and Portugal least of all. Portugal was hilly, and roads often bad. Maps and signposts left a lot to be desired. Staying in Portuguese towns was good though.
Hope to do this again next year. Probably Eurovelo 6 from Loire at Atlantic, to Vienna.