Saving files on a NAS

Hello,

I want to save a file on a NAS.
If I'm in a writer and I want to save it on a NAS, I get the message that I have not the permissions to save it on there.
The only way to get the file on the NAS is to first save it on the desktop en then drag the file from the desktop to the NAS.



How can I directly save a file on a NAS?

Thanks,
WDG