I have a pre-configured ctb file and I do not know how to insert it into CAD so it comes up when I plot and choose the pull down menu for plot style.
Go to Solution.
You'll need to copy it into your Autodesk Plot Style Manager folder via Control Panel. And restart Autocad.
How do I access the control panel?
You should have a start menu at the bottom left corner of your screen. Click on that and Control Panel is listed.
While in AutoCAD, type STYLESMANAGER command. The pop-up is where your AutoCAD looks for plot style tables. Drag and drop.
Restart AutoCAD, and assuming your DWG file is looking for CTB (and STB) it will work just fine.