Many of these differences are contained in the folder which Jonas brings home after he receives his Assignment.
He is now exempt from rules governing rudeness. In Jonas's community, it is rude to make anyone feel uncomfortable. Jonas learns that he can ask any question of anyone in the community, no matter how private, and receive answers. This allowance is not made for other Assignments.
Jonas is also forbidden to talk about his training with anyone in his community, including his parents. While his friends babble on about all they are learning, Jonas must remain quiet. There is so much that only he and the Giver understand because they are the ones who contain the memories; therefore, there is much about his training which would be impossible for anyone else to fathom. But because only he and the Giver hold the memories of the past for the community, it is important that he not share any information with anyone else.
Jonas no longer is required to participate in dream telling. Children are required to report dreams to their parents for help in sorting through issues. But because Jonas's dreams will now reflect his new understanding of the world which his parents do not share, he does not need to report dreams to them. The Giver effectively takes over as primary advisor in his life instead of his parents.
Becoming the Receiver of Memory will cause Jonas pain. Intense pain. Typically members of the community are spared any real pain, and when they are in discomfort, they are allowed medication to ease their symptoms. In his new role, Jonas is no longer allowed to take medication for pain; as Receiver, it is important that he fully understand all aspects of human suffering and the intense agony that humans can truly experience.
Jonas is also not allowed to request Release. This was likely added after the community's loss of Rosemary. When she realized the truth about both her training and the pain humans can cause, she applied for and was granted release, which she performed herself.
Finally, Jonas is allowed to lie, which is unfathomable to him. And this raises a larger question: Do other people have this same note in their packet of instructions? Is everyone lying while assuming that others speak only the truth?