This fictional story is just a representation of what the content might be like. If you're looking for the actual content, I recommend searching for it on legitimate platforms or websites that host idol-related videos and documentaries.
"Miyuu" (or Miyu) is a common name in the Japanese entertainment industry. Depending on the specific content, this could refer to: Miyu Kanade
The day begins early for Miyuu as she arrives at the group's practice studio. She meets up with her fellow members, and they start rehearsing their choreography for the concert. Miyuu is focused, but she's also feeling a bit nervous about the show. She's been struggling with her dance routine, and she's worried that she might not be good enough.