What Schema?

I have a website with a lot of pages about chords, and I'm facing a duplicate content issue because search engines can't tell the difference between similar chords like C#Maj and DbMaj. To solve this problem I want to add structured data to all my pages in bulk. Is there a plugin or tool that can help me do this, or a way to automatically generate the structured data based on the content of my pages? Also, I'm not sure which schema.org markup should I use for my musical chord pages, Can someone guide me on which schema.org type would be the most appropriate to describe my pages? Has anyone had a similar problem and found a solution to add structured data in bulk to avoid duplicate content issues?