Looking at the reference book while studying LPIC

$cp/@ etc/@ hosts/@myhosts
$ls @myhosts

I want to execute this command, but I get an error as shown in the image.
The tree command is executed on the image to see the hierarchy.
Certainly @etc and @hosts exist, but I get an error.

Error message
cp: cannot stat '/ @ etc/@ hosts': No such file or directory

Run the tree command
cd to root directory
Check with pwd
$cp/@ etc/@ hosts/@myhosts
An error will then occur.

Supplemental information (FW/tool version etc.)

pc: macbookair
os: high sierra
Version: 10.13.6

centos (download for learning from reference book)