Crafting Ashen Arrows, Ribs, Cooked Ribs and Wither Bone Meal
Ashen Arrow
Ashen Arrow is an ammunition item. Craft it at a crafting table and use it with a bow the same way you use any arrow. Carry a stack when you head into NetherEx terrain so you are not caught without ammo.
Ribs and Cooked Ribs
Ribs are a food item. Cook them to get Cooked Ribs, which restore more hunger than the raw form. Use a furnace or your Kiln to smelt Ribs into Cooked Ribs. Keep raw Ribs in a chest near your cooking station so you can batch-process them after a trip.
Wither Bone Meal
Wither Bone Meal is a bone-meal-style item. Use it the way you use regular bone meal: apply it to crops and plants to push growth. Stockpile it if you farm in or near the Nether, since it saves you from hauling bone meal from the Overworld.
A Simple Supply Loop
Set up one Kiln for bricks and a second station for food. Smelt Ribs into Cooked Ribs while your brick batches run. Keep Ashen Arrows and Wither Bone Meal in separate chests so you can grab them quickly before a fight or a planting session. Cooked Ribs are your travel food; Wither Bone Meal is your farm input; Ashen Arrows are your ranged option.