There are quite a few Cody and Sierra fanfics out there. Some focus on their romantic relationship, like 'Cody and Sierra: Forever Love'. It delves deep into how their feelings for each other grow over time. Then there are those that are more about their friendship, such as 'Cody and Sierra: Best Friends'. This one could show all the fun times they have together without any romantic undertones. There's also 'Cody and Sierra in the Spotlight' which might be about them becoming famous or something and how they handle it together.
First, think about their personalities. Cody is often seen as a bit of a geek but also very kind - hearted. Sierra is quite intense in her affections. Start with a simple plot idea, like them going on a date to a place they've never been. Then, just write down how they would interact, what they would say. For example, Cody might be nervous and stutter a bit at first.
I don't have enough information to say for sure. It could be fiction, or it could have roots in reality that have been adapted or exaggerated for a particular purpose.
The story of Anger Sierra might focus on Sierra's battles with her own anger, how it shapes her personality and the challenges she faces because of it. It could also involve her growth and transformation in dealing with this emotion.
I don't believe it's true. Most of the time, when a story has a name like that, it's made up to capture our interest and take us on a fictional journey rather than being rooted in reality.