Creating a path turning system

I am trying to get some scripting help from the professionals out there, I am having some issues on learning how to create a path turning system. Allow me to explain; When a player will place the path they’re will be a GUI on the side where there will be a line where the play can adjust a snap for when they press R on how it will rotate; meaning how far and how long the rotate will be.

I struggle with explaining as I am not very good at asking questions however this video should explain it much better:

We have tried to look up several times on how to get this yet we struggle so I come to the place where I can find scripters that can help us achieve our goal of getting this system implemented!