I can load Ominsphere on my Windows 10 computer just fine and hear notes via my Midi, but I would like to use the sounds in a piano roll in Fl Studio which is my DAW of choice. I'm hearing that I have to install Omnisphere like a plugin by locating it in the Steam folder, which I found, but when I scan the Steam folder for plugins, nothing related to Omnisphere is found. Please help.
The Steam folder contains all the samples and other support data for Omnisphere. When you install Omnisphere, you should also have installed any au,vsti or aaxi plugins that came with it. They will be getting installed in the usual place on your machine. Once you have done that, restart FL-Studio and you should be able to access it as a vsti in the normal way.