My wife and I walked our only camino, to date, last fall. I booked all of our lodgings, mostly private rooms in Albergues or Hostels. I booked all our nights between SJPdP and Pamplona before leaving home. After that, I booked two nights ahead, as we walked. I never had difficulty booking on my own and liked having the flexibility to short days and days off as we walked.
I would look for properties that listed a WhatsApp number, typed up my request in English, ran that through Google Translate into Spanish. Then I sent both, as a single message, to the property through WhatsApp. I usually got a response, even to say the rooms were booked. The few times I did not succeed that way, I used booking.com
Good Luck
Jim