I presume you are considering the
Camino Frances route, the most popular (there are many
Camino de Santiago routes). One can start anywhere along the route. To qualify for a Compostela certificate, you must show that you have walked at least the last 100 kilometers. The "whole path" of the
Camino Frances typically means starting at Saint Jean Pied de Port in southwestern France. Other common starting points are Roncesvalles and Pamplona, both in Spain.
And, if you are walking the
Camino Frances, you will be with many other people every day. I have walked that route twice, and I was never alone unless I wanted to be. I typically walked by myself the first couple of hours each morning as a sort-of morning meditation. Then I enjoyed the company of people I met, people from all over the world.
Is it safe? I cannot answer that from a woman's perspective, but it has been discussed on this forum many times. From my perspective, I felt safer on the Camino than anywhere; even a little safer than in my yoga-inspired trips to northern Thailand (Chiang Mai). Spain along the
Camino Frances is a wonderful place to be - and lends itself well to the inner aspects of the Camino pilgrimage, the meditative and introspective.
Buen Camino!
--jim--