显示/隐藏与fetch API反应的数据

I am trying to get data from an API and show/hide it on react. I get the data fine but hide button doesn't work. Data is shown always. I am relatively new to react and really want to learn it. Here is my code: (And it would be great if anyone suggest where can I learn more about react on web) I am trying to get data from an API and show/hi