What do you call a person who enacts, lives, or portrays the book he has read?
Solution 1:
Embodiment — M-W
someone or something that is a perfect representative or example of a quality, idea, etc.
"She's the embodiment of all our hopes."
"He's the embodiment of everything said in that book"
"men who greatly embodied the idealism of American life" — A. M. Schlesinger b1917
Such a person can be called an embodier.