Jonas was selected to be the receiver of memory. He has to hold all the wisdom and memories for the community.
Jonas's rules are that he goes there everyday, go to his dwelling after training hours, exempt from rudeness, can't talk about his training, can't discuss the training, can't tell about his dreams, can't use medication relating to his job, can't apply for release, and he can lie.
Why can't people make their own decisions?
The giver has books in his home and furniture that was not like the rest of the houses. He also has a lock on the door.
You can see the color red.
The giver transits memories of a sled, runners, snow, and coldness to Jonas. Another memory he gives him is of a sunburn and sunshine.
The community is not allowed to make decision because they can't make bad decision and it is easier to deal with. So, everyone has to be the same.
The giver describes seeing beyond as being able to see past what is there. Jonas is able to see color when everyone else sees none.