Note 3 Flashing another country's rom to update

I have a rooted Note 3 SM N900 with a Pakistani android 4.4 rom. I am thinking of flashing an Indian rom to update as lollipop is still not available in my country. However I can't seem to find definite info about CSC. Should I directly flash it or do i have to change CSC?
and also How do I back up my internal storage+apps+data?