You have to download an app to extract it (of course, don't just extract it, because it doesn't work like that).
You can download ZArchiver (it works perfectly), then you have to go to "Download" then on the top right corner there are 3 lines, click it and choose to organize in "Date" and go to the latest download (just scroll all the way down and search for it, it should be near). Then tap on it and click on the first option (aka Install) and it will start downloading.
You're welcome :) ❤️
(If it doesn't work, then there might be a problem and I won't be able to help. Sorry. At least I hope this helped <3)
Edit: If it tells you it didn't download after it seemed to, it's because of space on your phone. Always happens to me)