Guild Wars 2

If i transfer to another world, my characters and guild are transfered aswell? or i have to re-level a new toon and guild?

Your characters will move with you but any guild facilities will be left behind and you’ll start with zero influence on the new server.

if i then go back to my actual world, the guild will be how i left it?

just to clarify, im the leader of the guild.

Yes, it will be exactly as you left it.