The site you linked to (hxxps://cydia-app.com/) is unofficial, links to piracy and spyware sites, and should not be trusted. The official Cydia site is https://cydia.saurik.com/ but it doesn't include much information about Cydia and jailbreaks. To find out what jailbreaks are available for your device, check the r/Jailbreak wiki. (https://www.reddit.com/r/jailbreak/wiki/ios/canijailbreak)