Help with Gemini buld

Hello all.

I don't have a lot of experience playing POE 2 but I saw this build the other day and it looked like a lot of fun. If this is the wrong place to ask I apologize and please feel free to remove this post.

Floor is lava gemini build

My brother has been busting his ass helping me get gear for the build and getting it set up. The main issue currently is that survival seems pretty low. I get almost one shot in T14/T15 maps. Damage is fine but I can't seem to stay alive all that well.

POE Ninja Profile

This my character. If anyone could take a look and maybe tell me where I'm going wrong with gear/build, I would be greatly appreciative.