Tools > Print Production > Output Preview
That shows a preview of what separations would look like. It doesn't actually create separations.
What are you actually trying to do?
Create pre-separated PDF? Such workflows are not supported by Adobe products — in particular exporting PDF directly from InDesign or saving PDF directly from either Illustrator or Photoshop — and are not recognized by the industry as a best practice workflow since it requires preflattening all transparency and creating totally device-dependent (in terms of color and transparency flattening parameters) PDF.
If you are actually trying to do is print a full process color PDF file to separations (PostScript) from Acrobat, nothing has changed from Acrobat X to XI to DC. That aspect of the product is still the same.