Minecraft wiki entry for Defeating_a_bastion_remnant, associated text: Strong, durable armor of netherite tier, enchanted with Protection IV.
At least one piece of golden armor if you don't want piglins to aggravate. Please note that brutes will still attack you even with gold armor.
A sword and tools of at least diamond tier, enchanted with Sharpness V and Unbreaking II or better.
A bow, especially with the Power and/or Infinity enchantments, is very useful in dispatching piglins and piglin brutes with ease from a safe distance.
At least one shield, as they can prevent taking damage.
Food with high-enough saturation and hunger restoration. (such as steak, golden carrot, and cooked porkchops). Golden apples (optional) can heal the player quickly.
Bring some logs and/or planks to craft boats, which will be very useful against piglin brutes and melee piglins (see the Mobs section below on how to use them).
Expendable blocks you can easily obtain, place, and break. Good examples include dirt, cobblestone, and netherrack.
A pickaxe of at least diamond tier, to mine gold blocks if there are any. It is helpful to also enchant it with unbreaking II/III.
Potions can improve combat. Fire Resistance is incredibly useful, and can be obtained by simply bartering with piglins (optional).
Soul torches or other soul-fire items can be used to scare piglins (optional).
Gold to distract piglins and gather precious resources but not piglin brutes (ex. ender pearls)
TNT (optional), and a button (not flint and steel) to light the TNT.
Hoppers for looting chests without aggravating any piglins (optional).
Blocks of Iron and carved pumpkins for Iron Golems (optional).
Pistons and levers, buttons or redstone torches to move gilded blackstone from under chests so you can put hoppers there to get the items (optional).
A lava bucket to easily kill piglins and piglin brutes (optional).
A respawn anchor and glowstone, to respawn in the Nether (optional).