What role does freedom play as a possible theme or just a vehicle for Santiago's journey in The Alchemist?

I
think freedom works fairly well as a theme. It is quite a broad theme, but a supportable theme
nonetheless. I would recommend narrowing it down to personal freedom and/or free will. The story
focuses on Santiago, and readers know from early on in the story that Santiago is a character
that wants the freedom to pursue his own goals and dreams. That is one reason why he wanted to
be a shepherd in the first place. It allowed him to travel.

Once he set out
on his journey to achieve his Personal Legend, he is met with choice after choice of whether or
not to continue pursuing that goal. He even stagnates at one point, but Santiago always manages
to follow his own dream. His choices often result in bringing him danger, but Santiago is always
free to continue or quit. The book does a nice job of showing readers the benefits of chasing
after our dreams, and that isn't possible without free will and individual
freedom.