Question: dark souls 3 how to use pyromancy?
Answer: Go back to Firelink Shrine and speak with him, and he'll hand over a Pyromancy Flame and sell you a bunch of spells. Like all forms of magic in Dark Souls III, you'll need to attune them at a bonfire before you can use spells. Sit at a bonfire, attune magic, and you'll be able to equip spells in your available slots.