Story to get Pet Dog and Jellyfish in Elden Ring

First, you will need to rest on three Graces (outside of dungeon).

After that, get a horse whistle from Melina.

And fast travel to the Church of Elleh.

You will need to talk to witch Renna at Nightfall.

Tell her you got your Horse.

Get Spirit Calling Bell and Lone Wolf Ashes.

After that, you have to pass the time until morning and she is gone.

You will need to equip Wolf Ashes in a Pouch.

And get near enemies to activate the ashes.

After that, summon three wolves.

And go to Stormhill shack.

Keep Talking and Listening to Lady.

She then gives you Spirit Jellyfish Ashes.

Equip jellyfish Ashes and try it in Battle.