The chapter that you are looking for is the very, very end of the book, in chapter 31. If you haven't gotten that far in the book, I highly recommend it, because it all ties together in a super dramatic and super cool ending. Boo, the unlikely hero, is escorted home by Scout. She helps him along, as he is
"uncertain, as if her were not sure his hands and feet could make proper contact with the things he touched."
So, Scout, acting on all of the lessons in manners that her father and Calpurnia have taught her over the years, steps in to help him. After they go visit Jem, she walks him outside. At this point, he whispers, "Will you take me home?" He is a bit out of his element, and a bit scared, being in a new situation. So, Scout acquiescees, and offers him her arm, which he takes, and he walks "[Scout] down the sidewalk, as any gentleman would do."
I hope that helps a bit; again, I recommend reading the chapter on your own if you haven't yet. It is very touching, and gives us a full glimpse of the enigmatic Boo Radley that has been the subject of such fascination throughout the book.