How to save nano /usr/share/mupen64plus/InputAutoCfg.ini command in ssh

[btkieler]

https://wiki.recalbox.com/en/tutorials/controllers/configuration-of-customized-buttons/n64-controller-configuration

in these instructions when it states "if this file does not exist, it will be created with the above command." I have used the 'nano /usr/share/mupen64plus/InputAutoCfg.ini' command but its not letting me save my controller config

Any suggestions?