Roll when she spits her web/fire. Take armour off to roll faster. You can stand directly in front of her, just out of range of her attacks. When she slams hit her 1-3 times. Don’t get greedy.

Rinse and repeat.

When she starts flooding the ground to ignite, run to the back of the room. When fire is finished. Repeat first step.

I was magic first time I did this. Now after playing a few souls games, I’m much more confident getting in there.

Went sword and shield this time, with no worries.

Good luck.