Twitch Linking

How do I link my Twitch account? How do I unlink my accounts? What rewards do I get for linking? How do I know what Twitch streams are eligible to give rewards? How do I earn or unlock rewards? What rewards are available for Drops? How and when do I get my rewards? Help! I haven't received any rewards yet. How long do I have to watch in order to obtain a reward? As a streamer, how do I make sure my viewers can earn Drops from my stream? Do I have to watch a single stream without breaks to earn a Drop? Will there be more rewards/campaigns added in the future?