Q:

How to access dot directory

I’ve been googling on how to access dot directory in unix like system, but everybody is just talking about dot directories for this and that reason. I haven’t found anything on how to get to directory /mnt/fn/.system? See what is inside.
for instance
cd mnt

cd fn

and then what?

A:

.. and then cd .system. The presence of a dot at the start of really doesn't mean much of anything except to make it "hidden" - i.e. it won't appear in a default ls listing unless you specify -a.

A:

Dot meaning "this directory" dot dot meaning prev directory. 
When the file or directory start with dot meaning "hide"
"Hide" for ls or other commands, not for FS. So if you run ls /home/foo you don't see files or directory starting with dot.
If you run "rm -r /home/foo/*" all files will be delete. Not the files or directories starting with dot.
Now, in case of directory, this need execute permission, at least for owner. Doesn't matter if start with dot or not. X permission meaning "descend" o "execute".
Try remove x 

