Questions I didnt find answer in Ative Help

[Niwashi]

You can roll Need if your current job is able to equip that piece of loot, if not you can roll greed or pass.

Well, it's not actually based on whether you can equip it or not. It's based on whether the gear is designed for your job or not. At endgame, most gear is only equippable by the job(s) it's designed for, so that difference isn't as noticeable. While leveling, though, everyone can equip most mage gear and tanks can equip DoW damage dealer gear. But regardless of that, it's only your own role's gear where you'll have access to using a Need roll. Being able to equip another role's gear doesn't give you more loot options.

... a quest called An Ill-conceived Venture. It's found in all cities but I'm not sure if you need to complete the one found in your starting city.

You can do it in whichever city you wish, regardless of where you started.