I want to read. I want to go see family. I want to meet a guy. I want to hangout with friends. And I want to get smarter! I want to be able to do fun things. I want to get to know my family more. I want to remember my grandpa and remember the Christmas's I had with him. I want to make new friends.
I think the casket is a symbol of death and it is also a symbol of cruelty of the narrator that he took Doodle to see it and touch it to emphasize that they thought he was going to die so needed to be brought face to face with it.