You need broadcasting software either winamp or Sam broadcaster, I reccomend sam click
here and then download either 2 or 3, 2 is easier to work tbh.
Then once you've got that just keep sound settingss etc the same and work out how to add songs and you're all good.
Encoders are how you connect to the radio and once you've worked out Sam you should see on desktop B it has a box named "encoder". The information that goes in there is different for every site and ou won't be able to make an encoder until you get a job or trial so don't worry about that until then.