offset plane

I'm still learning how to use Onshape (I started yesterday, and I am still new to parametric CAD software). I'm having trouble with a resolve cut, and I don't know what is going on. I created a profile for a resolve cut in the middle of an object that I am modeling, and it worked great other than I had it on the top plane…

Hello there, I am currently trying to create a plane that is offset from the original. How can I do it in a script ?