Is nano available as a text editor in CFCD exam ?
Only VIM and emacs.
I know LFCS and LFCE exams permit access to packaging system software (e.g., yum, apt-get etc) but I don't know for CFCD exam. You should ask the people who do the certification, about this or maybe one of them is monitoring the forum and will answer. (It has been a long holiday in the USA)