How to get Netherite in Minecraft: from ancient debris to full gear
Every netherite item costs 4 Ancient Debris, 4 Gold Ingots and one upgrade template, applied to a diamond item.

Ancient Debris is the rare ore of the Nether, the only source of netherite.
It cannot be crafted; it can be found in chests. It is mined with a pickaxe (at least tier diamond).
It hides deep in the Nether, mostly in the lower layers, and is rarely exposed to air. It needs a diamond pickaxe, resists explosions, so bed or TNT mining is a common way to find it, and as an item it does not burn in lava. Smelt it into Netherite Scrap.
This item has no crafting recipe.
Every netherite item costs 4 Ancient Debris, 4 Gold Ingots and one upgrade template, applied to a diamond item.
Mining the block drops it. It can be found as loot in Bastion Remnant.
It is the rare Nether ore that gives netherite scrap. It is an ingredient in one recipe: Netherite Scrap.
The fastest tool is the pickaxe. It needs at least a diamond pickaxe.
No: as a dropped item it resists fire and lava.
Hidden in the Depths (Obtain Ancient Debris).