[Ask] Guild Wars platinum, Eye of North?

Ok, so I bought Guild Wars platinum and installed it, and sez that Guild Wars and Eye of North have been installed.

I'm wondering why I cannot pick professions from Eye of North... Do I have to finnish the Guild Wars campaign first?

There aren't any new professions in EotN, and you can't start a character in it. It's all designed for characters that are level 20 from a previous chapter.

Eye of the North is an expansion, meaning you can't make characters there.

You have to get to Lion's Arch/Kamadan/Kaineng center first, and then a little box will pop up saying talk to so and so to get the quest to get to Eye of the North.

What about Nightfall and Factions? Is that an expansion or a completely different game?

Those are completely different games meaning you can make characters in them.

But then again; you can travel to the other campaigns with characters from different campaigns. So if you make a char in Prophecies (Tyria) you can at a certain point go to Nightfall and Factions (if you add those to the same account).

prophecies, factions and nightfall are complete chapters in the guildwars saga, the eye of the north is an expansion..meaning you must own one of the complete chapters for it to work and that there are no new professions or character creation in it.
You can have all 3 chapters and the expansion on one account (which is suggested---if you get a new chapter just sign in on your original account and go to manage keys and add the new cd key).
The three chapters can be linked and characters created in any of them can travel to any of the others that you have linked to your account.

So if you have a dervish (only available in nightfall) and you own prophecies he can travel to prophecies and play there, if you add factions to your account he can travel there as well, and seeing as you said you own eye once he reaches level 10 he can travel to it as well.

Hope this helps