There are a lot of fake versions of Danker's Skyblock Mod. The correct one is at https://github.com/bowser0000/SkyblockMod
Please, if something on GitHub does not have its source code public, don't use it, or at least do your research. There are quite a few of these fake repos popping up, so please don't fall for them
(make an issue or a PR if you have another for me to add)
Danker's Skyblock Mod: https://github.com/bowser0000/SkyblockMod
Skytils: https://github.com/Skytils/SkytilsMod
Cowlection: https://github.com/cow-mc/Cowlection/
SkyBlockAddons: https://github.com/BiscuitDevelopment/SkyblockAddons
NotEnoughUpdates (official): https://github.com/Moulberry/NotEnoughUpdates
NotEnoughUpdates (unofficial): https://github.com/NotEnoughUpdates/NotEnoughUpdates