Save Brush Setting

I recently purchased a Surface Book and am using Lightroom Desktop on it. I previously worked on a Mac, so it's a little different than I am used to. The issue I am facing is that I have a brush that I am using for teeth whitening. I want to save it so that I can quickly use those settings on other photos. I cannot figure out how to save a brush in Lightroom in Windows. I've watched tutorials online but their lightroom screen looks different. See attached screenshot for mine. Anyone know how to do this?