What is Linda able to teach John? What does the Pope give john shortly after his twelfth birthday?

Linda teaches John to read. As for the second part of your question....

One day (John calculated later that it must have been soon after his twelfth birthday) he came home and found a book that he had never seen before lying on the floor in the bedroom. It was a thick book and looked very old. The binding had been eaten by mice; some of its pages were loose and crumpled. He picked it up, looked at the title-page: the book was called The Complete Works of William Shakespeare.