How would I get to Nazjatar?

[Nobully-blackrock (Nobully)]

no.
that portal goes to Vash’jir.

@Udiza-earthen-ring

• Get your Heart of Azeroth. The Earthen Guardian NPC will have the quest “A Dying World” to start this. For Alliance, the NPC is near the Boralus Inn. For Horde, they are near the Zuldazar Harbor flightpath. Then complete “The Heart of Azeroth” and “Infusing the Heart” from Magni.
• Unlock World Quests. The quest you need to complete for this is “Uniting Kul Tiras” (A)/“Uniting Zandalar” (H). On your first character, you’ll need to do the 3 foothold quests of the War Campaign to unlock the boat travel to the 3 zones of the other faction for this quest to be available.
• Unlock Naz’jatar. Head to the boat and pickup “Send the Fleet” from Nathanos (H) / Genn (A).