Important Note: it is very important to know first how to give permissions of CMS before explaining how to edit them. For example, if you give a group of users permission to login to a section of Blog module, and prevent them from logging to the module it self, this group will be able to login to the section. As a result, you prevent them from logging to the module, they can not login into any section of the module. On the contrary, what is true is to give the user a permission to the whole module and then define certain sections to cancel their permissions, so that the user will be able to login to the required ones.
To sum up, all CMS permissions are divided into levels, the priority is for the highest level.
To edit section permissions, follow the below steps:
Press the icon (Edit permissions) in front of the required section as shown in the below picture:
A list of all available permissions will show up. At the top of the list, there is an icon to activate or deactivate all permission as shown below:
Each permission has a dropdown list of the users groups to select which group will get this permission, or press (Select all) to give this permission to all groups as the below picture: