change permissions of all folders and sub folders
 

Please tell me if there is a command to change the permissions of all subfolders and files in folders and subfolders

chmod -R changes permissions recursively

See man chmod

Recursive:
would take recursively eXecution permissions off from "other" users (than owner or owner group). So just use chmod (or chown for owners) with the -R flag to make it run recursively, i.e. do the job for all sub-files and -diretories (directories are, by the way, only special files on UNIX).