To see the directory and file list
ls
To see the permission status of linux file/folder
ls -l
To change the permission for others
sudo chmod o+wx filename
here to add permission use ‘+’ and to remove permission use ‘-’. Secondly, o means others, g means group, u mean owner and a for all. [r means read, w means write and x means execute, chmod means change mode]
To set the permission
sudo chmod a = rwx filename
Absolute mode permission
sudo chmod 755 file/foldername
To install a apps( Here I am installing google chrome)
sudo apt install ./google-chrome-stable_current_amd64.deb