Where do you get Quests in Sea of Thieves?

Excuse me, could you possibly elaborate on the mechanics of acquiring Quests within the game of Sea of Thieves? I'm particularly curious about the various locations or methods through which players can come across and initiate these Quests. Is there a specific NPC or hub where they're typically found, or do they perhaps appear randomly throughout the game world? I'd appreciate any insights you might have on this matter.