Prism's nonlinear regression dialog has ten tabs, explained here. It can seem overwhelming at first. But you don't have to learn about all the choices when you first fit a curve. Start by focussing on the choices in the first (Fit) tab, and then learn about the other choices later.

•Before learning all the details, first understand the big picture -- the basic steps required to fit a model to data.

•So many choices! Which ones are essential?