If you are using Virtuoso from cadence you can do the following:
1.from the schematic open Tools-Analog environment
2. From the Analog environment window open Tools-Monte CArlo
3. You get a pop-up window where you can choos #of runs, analysis variation, param swept and signals to be shown
Partially you are right. Better processes tend to have less absolute variation. However, mismatch is usually a different story and depends entirely on your layout. End of story 2 structures(Caps, resistors) can vary a lot due to the process(+/-30% even 50%), but relative to each other you can have less than1-2% variance