File upload

Maybe I have just been staring at my computer for too long, but when I download the zip file and attempt to upload under Plugins in word press, the upload screen wants me to choose a specific file in the zip file.

What am I doing wrong? Shouldn’t I be able to upload the whole zip file?
I have unzipped it by the way too and that makes no difference.

Jackie

https://ww.wp.xz.cn/plugins/custom-sidebars/