Okay, so imagine you and your friends are playing on a playground, but then a bigger kid comes and starts telling you all what to do. You don't like it because you want to play your own games and do what you want.
This is kind of what happened in Ukraine. There were some people in charge, called regional state administrations, who were telling other people what to do and making decisions about their lives. Some of the people didn't like this because they wanted to make their own choices and have more control over their communities.
So, they decided to protest by occupying the regional state administration buildings. This means they gathered together and stayed inside the buildings, not allowing the people in charge to enter or leave. They wanted to show that they were unhappy with the way things were being run and that they wanted to have more say in how their communities were run.
These occupations happened in different cities and regions of Ukraine, and it was a big deal because it showed that people were not happy with the way things were going and wanted change. It also led to bigger events, like protests and even conflict, which had a big impact on Ukraine's future.