I would like to change permissions of a folder and all its sub folders and files in one step (command) in Linux.
I have already tried the below command but it works
You can use -R with chmod for recursive traversal of all files and subfolders.
-R
chmod
You might need sudo as it depends on LAMP being installed by the current user or another one:
sudo chmod -R 755 /opt/lampp/htdocs