ls command doesn't show folder but I can't create it because folder already exists

ls by itself does not show hidden directories (hidden directories and files are ones that start with a ., such as .ssh)

Try using ls -a in the directory.

From the ls manpage:

-a, --all

do not ignore entries starting with .

As noted in the comments, "hidden" directories and files are not technically a thing, there is just code built into a lot of common tools that treat . and .. with special meaning, the result being that . is usually considered "hidden" by most tools. The reason I used this term is because it's common to hear it referred to that way.

Additionally . and .. usually have special meaning to most filesystems, indicating current directory and parent directory, respectively.

In your step 3, type ls -a to list the contents of directory.

File or directory whose name starts with . will be ignored by ls.