I have seen kits advertised but I have no idea what they are or what they do, even how to get them, please help

 

Read all the descriptions here: Skyblock | Welcome
It talks about what comes in the donor kits and the other kits that you can purchase.
Kits are basically gifts that you get from donating.

 

you can buy kits/donate here Skyblock | Welcome

 

Kits can come with Donor packages, but you can but kits seperatley such as the Mob Spawner kit or Wool kit.