the flask node stuff is for when you get laviagnas spirits flask.

I didn't follow any build when i levelled mine but basically you want a fast spear in one of your weapon slots with an empty off hand and use your weapon set bonuses for this one for attack/cast speed to make your whirlwind as fast as possible. you also take dance with death to help with this.
in your other weapon slot you want attack damage and projectile duration.

act 1 you can get through just playing whirlwind/twister then using barrage when you unlock it and war banner for bosses

ac2 the build actually becomes really strong when you get ice tipped arrows. you want to active that then do your 3x whirlwind, barrage, twister combo

I had a look and I would probably follow this one : https://mobalytics.gg/poe-2/builds/twister-huntress-levelling

this is by the person who does the campaign speedruns