What was the 95 theses? What were the 3 main criticisms of the Catholic Church?

The 95 theses was a list of things that Martian Luther found wrong with the doctrines of the Catholic church. Luther believed that the Catholic church was wrong to worship Mary, he also believed that people should be able to read the Bible for themselves, and he had several other concerns about the way the church was run. He then nailed the 95 theses to the door of the catholic church where everybody could see it, which led to several events that helped contribute to the freedom of worship that we have today.

Hope this helps, sorry that I was not sure about the main criticisms