If you want to learn how to do stuff like terraform with world edit and use commands and modpacks a way to do that is by going on a server that has staff that will actually teach you and give you the perms to do it. Reading about it and doing it are 2 different things. I reccomend the server that is on the banner below as a start because it is not too big that the players get ignored and not too small that there is no one on to show you. The staff are helpful. Good Luck! To terraform log on and do /server creative to get builder, fly, a plot and world edit to begin with immediately then ask for one of the owners to show you commands.

Thanks Zezill, i seem to have a loadout issue where i get log data in the loadout tab on both my forge & modloader profile when i press play. i also seem to have lost the mods button in the menu.

Your best option to find people to play with online is through a Modpack. Like Voltz..
You can get some pretty popular modpacks through http://www.feed-the-beast.com/ or http://www.technicpack.net/ both of these are their own clients for minecraft and help manage them and keep them up to date.
Some of the modpacks after having them installed will include some sponsored servers. It's pretty useful for when your starting off for the first time!