Linux File Permissions - CameronProvost/Tech-Journal GitHub Wiki
Add a new user - useradd "user"
Create a new group - groupadd "group"
Add user to group - usermod -aG "group" "user"
Add group to directory - chgrp "group" "/directory"
To add permissions to a group/directory - chmod g+"permission either r/w/x" "/directory/"
To remove permissions for others - chmod o-rwx "/directory/"