How to play games on Minecraft?

I'm a Minecraft noob and I have the pc version. I want to play the diversity game and to do that I have to install a folder or whatever but I don't know what to do with that folder. Please don't tell me I have to pay more money or something T-T Thank you!

Added (1). Oh and it's not a game where there's a server IP btw.

Guest

Ok, first download the map you want.
Press cmd+r
Type %appdata%
Double click on the.minecraft folder
Drop the map into the saves folder, but make sure you have the map as a folder and not a.zip file.
If it is a.zip, download winrar.

Michael