Guild Wars 2

Hi

New to the game.
Does the race give any bonuses on profession?
Example, is a Norn warrior better then a human warrior?
If one makes a necromancer should one choose e special race in front of another?

Or is it just so that the race is to make the gameplay interaction more diversified?

No, there are no racial bonuses in the game because A-net wants players to create whatever characters they want without being pigeonholed.

There are racial skills that you can use in PvE and WvW (not sPvP), but generally (at least the elites) they are weaker than profession skills. There are a few specific exceptions.