Hi senora1. I checked out the link and it looks like a great bike. Make sure you can get your leg over easily which, given your age, you almost certainly can. I rode the Camino on a similar one which weighed about the same, although we didn't fly to St John Pied de Port.
You could definitely ride parts of the Camino on it depending if you are intending to carry your gear at the same time. If you keep to around 40 km a day you can also stop off and see things that you might otherwise miss.
I rode the
Camino de Santiago back in 2013 with my husband. I was 65, he was 72. It was tough some of the time, particularly the hills, but such an amazing experience. If you are interested, have a look at
www.cyclingsofties.blog. You would also get an idea of the terrain in places.
Although I had some knee trouble and the upper thigh on my left leg caused some consternation, having painkillers and creams went a long way. We all work around it, don't we. Riding day after day is completely different to riding on and off, as I soon discovered!
Like you, I have arthritis and have actually invested now in an electric bike. The doctor advised that it was either that or forget about cycling altogether which wasn't an option as I enjoy it.
Another option might be to buy a cheap bike when you arrive and give it away at the other end, or sell it to one of the bike shops once you reach Santiago, and before you fly back home. But I have to admit I wouldn't do that because I think it's a matter of being happy with what you are riding. Be aware that, on the first few days at least, you might find yourself walking and pushing the bike up some steep places. Indeed, I think we walked most of the way up to Roncesvalles on the first day
.
Don't give up on the idea, as I am sure the Camino is calling you back. I would say, just go and do it.