Bmlegolas Erika 1 Lightning shot help

I am currently playing a Erika 1 Lightning shot build by Bmlegolas.

It's my first season and I have now gotten a bit stuck at TM 8.2 and could use some help.

I have about 200b-250b DPS, but i can't see how the build gets trillions of DPS and i am unsure about what to spend my FE on.

I have looked through the document, but sadly I am unsure about what would be smart to focus on.

One other thing, I am also looking for something to farm as i only have legendary level 1 key of Overrealm and level 1 Monument knight pact spirits.

Build: YxW+W0y8EfGEWAAAAAAAUg==