Photoshop cs6 doesn't have the Filter>Camera Raw Filter.
That is available only in photoshop cc or cc 2014
If you have cs6 (may work with others but never tried). A little trick I do to open my jpeg in camera raw is the following:
1. In photoshop select File > Open
2. Select the file you want to open in camera Raw
3. In the format drop down at the bottom, change it to camera raw
4. Hit open
that's it your in camera raw with the JPEG
Image for visual:
Hope this Helps!