Amarissa O. answered 06/27/19
Supportive and Relational Outlook on Tutoring
That's so unbelievably relatable. Something that helped me was joining an intensive creative writing class where I had deadlines to write the story, so I had to submit something even if it was garbage. Though the submission might be garbage, it was at least a complete story, so I could begin working that piece of trash into something better.
If you're made of time and money, I'd recommend a live web-conference course with Harvard. They have limited enrollment, which means that you get 1-1 care from professors. But it also means that the classes fill up the week that sign ups become available, so sign up fast. https://www.extension.harvard.edu/course-catalog/courses/introduction-to-fiction-writing/13774?subjects=Creative%20Writing&format=Online%20%28live%29%20web%20conference
Probably, your side ideas are amazing and you should try them out even though they are different from your main plot. What I personally do is start with an entire outline of my story-- which is subject to change-- but I follow that outline as closely as makes sense when I sit down to write the story. Then, I have a document called "scraps." In my scraps document for each story, I write out those side ideas. They might be complete or incomplete, but I write them out to the fullness of what's in my brain. Then, I let the scraps lay in that document. After working on the main story, if a scrap is sticking out in my mind, I'll go and find it and add it to the actual story.